diff --git a/src/fraggle/fraggle_generate.f90 b/src/fraggle/fraggle_generate.f90
index 486aed2ea..af10af236 100644
--- a/src/fraggle/fraggle_generate.f90
+++ b/src/fraggle/fraggle_generate.f90
@@ -39,10 +39,10 @@ module subroutine fraggle_generate_fragments(self, colliders, system, param, lfa
       associate(frag => self, nfrag => self%nbody, pl => system%pl)
 
          write(message,*) nfrag
-         call fraggle_io_log_one_message("Fraggle generating " // trim(adjustl(message)) // " fragments.")
+         call io_log_one_message(FRAGGLE_LOG_OUT, "Fraggle generating " // trim(adjustl(message)) // " fragments.")
          if (nfrag < NFRAG_MIN) then
             write(message,*) "Fraggle needs at least ",NFRAG_MIN," fragments, but only ",nfrag," were given."
-            call fraggle_io_log_one_message(message)
+            call io_log_one_message(FRAGGLE_LOG_OUT, message)
             lfailure = .true.
             return
          end if
@@ -64,7 +64,7 @@ module subroutine fraggle_generate_fragments(self, colliders, system, param, lfa
          try = 1
          do while (try < MAXTRY)
             write(message,*) try
-            call fraggle_io_log_one_message("Fraggle try " // trim(adjustl(message)))
+            call io_log_one_message(FRAGGLE_LOG_OUT, "Fraggle try " // trim(adjustl(message)))
             if (lfailure) then
                call frag%restructure(colliders, try, f_spin, r_max_start)
                call frag%reset()
@@ -87,19 +87,19 @@ module subroutine fraggle_generate_fragments(self, colliders, system, param, lfa
 
             call fraggle_generate_spins(frag, colliders, f_spin, lfailure)
             if (lfailure) then
-               call fraggle_io_log_one_message("Fraggle failed to find spins")
+               call io_log_one_message(FRAGGLE_LOG_OUT, "Fraggle failed to find spins")
                cycle
             end if
 
             call fraggle_generate_tan_vel(frag, colliders, lfailure)
             if (lfailure) then
-               call fraggle_io_log_one_message("Fraggle failed to find tangential velocities")
+               call io_log_one_message(FRAGGLE_LOG_OUT, "Fraggle failed to find tangential velocities")
                cycle
             end if
 
             call fraggle_generate_rad_vel(frag, colliders, lfailure)
             if (lfailure) then
-               call fraggle_io_log_one_message("Fraggle failed to find radial velocities")
+               call io_log_one_message(FRAGGLE_LOG_OUT, "Fraggle failed to find radial velocities")
                cycle
             end if
 
@@ -110,14 +110,14 @@ module subroutine fraggle_generate_fragments(self, colliders, system, param, lfa
             lfailure = ((abs(dEtot + frag%Qloss) > FRAGGLE_ETOL) .or. (dEtot > 0.0_DP)) 
             if (lfailure) then
                write(message, *) dEtot, abs(dEtot + frag%Qloss) / FRAGGLE_ETOL
-               call fraggle_io_log_one_message("Fraggle failed due to high energy error: " // trim(adjustl(message)))
+               call io_log_one_message(FRAGGLE_LOG_OUT, "Fraggle failed due to high energy error: " // trim(adjustl(message)))
                cycle
             end if
 
             lfailure = ((abs(dLmag) / (.mag.frag%Ltot_before)) > FRAGGLE_LTOL) 
             if (lfailure) then
                write(message,*) dLmag / (.mag.frag%Ltot_before(:))
-               call fraggle_io_log_one_message("Fraggle failed due to high angular momentum error: " // trim(adjustl(message)))
+               call io_log_one_message(FRAGGLE_LOG_OUT, "Fraggle failed due to high angular momentum error: " // trim(adjustl(message)))
                cycle
             end if
 
@@ -126,14 +126,14 @@ module subroutine fraggle_generate_fragments(self, colliders, system, param, lfa
             lfailure = any(fpe_flag) 
             if (.not.lfailure) exit
             write(message,*) "Fraggle failed due to a floating point exception: ", fpe_flag
-            call fraggle_io_log_one_message(message)
+            call io_log_one_message(FRAGGLE_LOG_OUT, message)
          end do
 
          write(message,*) try
          if (lfailure) then
-            call fraggle_io_log_one_message("Fraggle fragment generation failed after " // trim(adjustl(message)) // " tries")
+            call io_log_one_message(FRAGGLE_LOG_OUT, "Fraggle fragment generation failed after " // trim(adjustl(message)) // " tries")
          else
-            call fraggle_io_log_one_message("Fraggle fragment generation succeeded after " // trim(adjustl(message)) // " tries")
+            call io_log_one_message(FRAGGLE_LOG_OUT, "Fraggle fragment generation succeeded after " // trim(adjustl(message)) // " tries")
             call fraggle_io_log_generate(frag)
          end if
 
@@ -254,16 +254,16 @@ subroutine fraggle_generate_spins(frag, colliders, f_spin, lfailure)
          lfailure = ((frag%ke_budget - frag%ke_spin - frag%ke_orbit) < 0.0_DP)
 
          if (lfailure) then
-            call fraggle_io_log_one_message(" ")
-            call fraggle_io_log_one_message("Spin failure diagnostics")
+            call io_log_one_message(FRAGGLE_LOG_OUT, " ")
+            call io_log_one_message(FRAGGLE_LOG_OUT, "Spin failure diagnostics")
             write(message, *) frag%ke_budget
-            call fraggle_io_log_one_message("ke_budget     : " // trim(adjustl(message)))
+            call io_log_one_message(FRAGGLE_LOG_OUT, "ke_budget     : " // trim(adjustl(message)))
             write(message, *) frag%ke_spin
-            call fraggle_io_log_one_message("ke_spin       : " // trim(adjustl(message)))
+            call io_log_one_message(FRAGGLE_LOG_OUT, "ke_spin       : " // trim(adjustl(message)))
             write(message, *) frag%ke_orbit
-            call fraggle_io_log_one_message("ke_orbit      : " // trim(adjustl(message)))
+            call io_log_one_message(FRAGGLE_LOG_OUT, "ke_orbit      : " // trim(adjustl(message)))
             write(message, *) frag%ke_budget - frag%ke_spin - frag%ke_orbit
-            call fraggle_io_log_one_message("ke_remainder  : " // trim(adjustl(message)))
+            call io_log_one_message(FRAGGLE_LOG_OUT, "ke_remainder  : " // trim(adjustl(message)))
          end if
 
       end associate
@@ -355,20 +355,20 @@ subroutine fraggle_generate_tan_vel(frag, colliders, lfailure)
          ! If we are over the energy budget, flag this as a failure so we can try again
          lfailure = ((frag%ke_budget - frag%ke_spin - frag%ke_orbit) < 0.0_DP)
          if (lfailure) then
-            call fraggle_io_log_one_message(" ")
-            call fraggle_io_log_one_message("Tangential velocity failure diagnostics")
+            call io_log_one_message(FRAGGLE_LOG_OUT, " ")
+            call io_log_one_message(FRAGGLE_LOG_OUT, "Tangential velocity failure diagnostics")
             call frag%get_ang_mtm()
             L_frag_tot = frag%L_spin(:) + frag%L_orbit(:)
             write(message, *) .mag.(frag%L_budget(:) - L_frag_tot(:)) / (.mag.frag%Ltot_before(:))
-            call fraggle_io_log_one_message("|L_remainder| : " // trim(adjustl(message)))
+            call io_log_one_message(FRAGGLE_LOG_OUT, "|L_remainder| : " // trim(adjustl(message)))
             write(message, *) frag%ke_budget
-            call fraggle_io_log_one_message("ke_budget     : " // trim(adjustl(message)))
+            call io_log_one_message(FRAGGLE_LOG_OUT, "ke_budget     : " // trim(adjustl(message)))
             write(message, *) frag%ke_spin
-            call fraggle_io_log_one_message("ke_spin       : " // trim(adjustl(message)))
+            call io_log_one_message(FRAGGLE_LOG_OUT, "ke_spin       : " // trim(adjustl(message)))
             write(message, *) frag%ke_orbit
-            call fraggle_io_log_one_message("ke_tangential : " // trim(adjustl(message)))
+            call io_log_one_message(FRAGGLE_LOG_OUT, "ke_tangential : " // trim(adjustl(message)))
             write(message, *) frag%ke_budget - frag%ke_spin - frag%ke_orbit
-            call fraggle_io_log_one_message("ke_radial     : " // trim(adjustl(message)))
+            call io_log_one_message(FRAGGLE_LOG_OUT, "ke_radial     : " // trim(adjustl(message)))
          end if
       end associate
 
@@ -515,16 +515,16 @@ subroutine fraggle_generate_rad_vel(frag, colliders, lfailure)
 
          lfailure = abs((frag%ke_budget - (frag%ke_orbit + frag%ke_spin)) / frag%ke_budget) > FRAGGLE_ETOL
          if (lfailure) then
-            call fraggle_io_log_one_message(" ")
-            call fraggle_io_log_one_message("Radial velocity failure diagnostics")
+            call io_log_one_message(FRAGGLE_LOG_OUT, " ")
+            call io_log_one_message(FRAGGLE_LOG_OUT, "Radial velocity failure diagnostics")
             write(message, *) frag%ke_budget
-            call fraggle_io_log_one_message("ke_budget     : " // trim(adjustl(message)))
+            call io_log_one_message(FRAGGLE_LOG_OUT, "ke_budget     : " // trim(adjustl(message)))
             write(message, *) frag%ke_spin
-            call fraggle_io_log_one_message("ke_spin       : " // trim(adjustl(message)))
+            call io_log_one_message(FRAGGLE_LOG_OUT, "ke_spin       : " // trim(adjustl(message)))
             write(message, *) frag%ke_orbit
-            call fraggle_io_log_one_message("ke_orbit : " // trim(adjustl(message)))
+            call io_log_one_message(FRAGGLE_LOG_OUT, "ke_orbit : " // trim(adjustl(message)))
             write(message, *) frag%ke_budget - (frag%ke_orbit + frag%ke_spin)
-            call fraggle_io_log_one_message("ke_remainder  : " // trim(adjustl(message)))
+            call io_log_one_message(FRAGGLE_LOG_OUT, "ke_remainder  : " // trim(adjustl(message)))
          end if
 
       end associate
diff --git a/src/fraggle/fraggle_io.f90 b/src/fraggle/fraggle_io.f90
index dbd721216..9d7af73f1 100644
--- a/src/fraggle/fraggle_io.f90
+++ b/src/fraggle/fraggle_io.f90
@@ -61,24 +61,24 @@ module subroutine fraggle_io_log_generate(frag)
    end subroutine fraggle_io_log_generate
 
 
-   module subroutine fraggle_io_log_one_message(message)
-      !! author: David A. Minton
-      !!
-      !! Writes a single message to the fraggle log file
-      implicit none
-      ! Arguments
-      character(len=*), intent(in) :: message
-      ! Internals
-      character(STRMAX) :: errmsg
-
-      open(unit=FRAGGLE_LOG_UNIT, file=FRAGGLE_LOG_OUT, status = 'OLD', position = 'APPEND', form = 'FORMATTED', err = 667, iomsg = errmsg)
-      write(FRAGGLE_LOG_UNIT, *) trim(adjustl(message)) 
-      close(FRAGGLE_LOG_UNIT)
-
-      return
-      667 continue
-      write(*,*) "Error writing Fraggle message to log file: " // trim(adjustl(errmsg))
-   end subroutine fraggle_io_log_one_message
+   ! module subroutine io_log_one_message(FRAGGLE_LOG_OUT, message)
+   !    !! author: David A. Minton
+   !    !!
+   !    !! Writes a single message to the fraggle log file
+   !    implicit none
+   !    ! Arguments
+   !    character(len=*), intent(in) :: message
+   !    ! Internals
+   !    character(STRMAX) :: errmsg
+
+   !    open(unit=FRAGGLE_LOG_UNIT, file=FRAGGLE_LOG_OUT, status = 'OLD', position = 'APPEND', form = 'FORMATTED', err = 667, iomsg = errmsg)
+   !    write(FRAGGLE_LOG_UNIT, *) trim(adjustl(message)) 
+   !    close(FRAGGLE_LOG_UNIT)
+
+   !    return
+   !    667 continue
+   !    write(*,*) "Error writing Fraggle message to log file: " // trim(adjustl(errmsg))
+   ! end subroutine fraggle_io_log_one_message
 
 
    module subroutine fraggle_io_log_pl(pl, param)
@@ -228,28 +228,28 @@ module subroutine fraggle_io_log_regime(colliders, frag)
    end subroutine fraggle_io_log_regime
 
 
-   module subroutine fraggle_io_log_start(param)
-      !! author: David A. Minton
-      !!
-      !! Checks to see if the Fraggle log file needs to be replaced if this is a new run, or appended if this is a restarted run
-      implicit none
-      ! Arguments
-      class(swiftest_parameters), intent(in) :: param
-      ! Internals
-      character(STRMAX) :: errmsg
-      logical           :: fileExists
-
-      inquire(file=FRAGGLE_LOG_OUT, exist=fileExists)
-      if (.not.param%lrestart .or. .not.fileExists) then
-         open(unit=FRAGGLE_LOG_UNIT, file=FRAGGLE_LOG_OUT, status="REPLACE", err = 667, iomsg = errmsg)
-         write(FRAGGLE_LOG_UNIT, *, err = 667, iomsg = errmsg) "Fraggle logfile"
-      end if
-      close(FRAGGLE_LOG_UNIT)
-
-      return
-
-      667 continue
-      write(*,*) "Error writing Fraggle log file: " // trim(adjustl(errmsg))
-   end subroutine fraggle_io_log_start
+   ! module subroutine fraggle_io_log_start(param)
+   !    !! author: David A. Minton
+   !    !!
+   !    !! Checks to see if the Fraggle log file needs to be replaced if this is a new run, or appended if this is a restarted run
+   !    implicit none
+   !    ! Arguments
+   !    class(swiftest_parameters), intent(in) :: param
+   !    ! Internals
+   !    character(STRMAX) :: errmsg
+   !    logical           :: fileExists
+
+   !    inquire(file=FRAGGLE_LOG_OUT, exist=fileExists)
+   !    if (.not.param%lrestart .or. .not.fileExists) then
+   !       open(unit=FRAGGLE_LOG_UNIT, file=FRAGGLE_LOG_OUT, status="REPLACE", err = 667, iomsg = errmsg)
+   !       write(FRAGGLE_LOG_UNIT, *, err = 667, iomsg = errmsg) "Fraggle logfile"
+   !    end if
+   !    close(FRAGGLE_LOG_UNIT)
+
+   !    return
+
+   !    667 continue
+   !    write(*,*) "Error writing Fraggle log file: " // trim(adjustl(errmsg))
+   ! end subroutine fraggle_io_log_start
 
 end submodule s_fraggle_io
\ No newline at end of file
diff --git a/src/fraggle/fraggle_regime.f90 b/src/fraggle/fraggle_regime.f90
index df9265ae7..f53888df5 100644
--- a/src/fraggle/fraggle_regime.f90
+++ b/src/fraggle/fraggle_regime.f90
@@ -182,7 +182,7 @@ subroutine fraggle_regime_collresolve(Mcb, m1, m2, rad1, rad2, xh1, xh2, vb1, vb
          Mlr = Mtot
          Mslr = 0.0_DP
          Qloss = 0.0_DP
-         call fraggle_io_log_one_message("Fragments would have mass below the minimum. Converting this collision into a merger.")
+         call io_log_one_message(FRAGGLE_LOG_OUT, "Fragments would have mass below the minimum. Converting this collision into a merger.")
       else 
          if( Vimp < Vescp) then
             regime = COLLRESOLVE_REGIME_MERGE !perfect merging regime
diff --git a/src/io/io.f90 b/src/io/io.f90
index ef3f682d2..b0f30d802 100644
--- a/src/io/io.f90
+++ b/src/io/io.f90
@@ -101,7 +101,6 @@ module subroutine io_dump_param(self, param_file_name)
       class(swiftest_parameters),intent(in) :: self    !! Output collection of parameters
       character(len=*),          intent(in) :: param_file_name !! Parameter input file name (i.e. param.in)
       ! Internals
-      integer(I4B), parameter  :: LUN = 7       !! Unit number of output file
       character(STRMAX)        :: errmsg !! Error message in UDIO procedure
       integer(I4B)             :: ierr
 
@@ -160,7 +159,6 @@ module subroutine io_dump_particle_info_base(self, param, idx)
 
       ! Internals
       logical, save             :: lfirst = .true.
-      integer(I4B), parameter   :: LUN = 22
       integer(I4B)              :: i
       character(STRMAX)         :: errmsg
 
@@ -228,7 +226,6 @@ module subroutine io_dump_base(self, param)
       class(swiftest_parameters), intent(inout) :: param !! Current run configuration parameters 
       ! Internals
       integer(I4B)                   :: ierr    !! Error code
-      integer(I4B),parameter         :: LUN = 7 !! Unit number for dump file
       integer(I4B)                   :: iu = LUN
       character(len=:), allocatable  :: dump_file_name
       character(STRMAX)              :: errmsg 
@@ -395,7 +392,6 @@ module function io_get_old_t_final_system(self, param) result(old_t_final)
       ! Internals
       class(swiftest_nbody_system), allocatable :: tmpsys
       class(swiftest_parameters),   allocatable :: tmpparam
-      integer(I4B), parameter :: LUN = 76
       integer(I4B) :: ierr, iu = LUN
       character(len=STRMAX)            :: errmsg
 
@@ -411,6 +407,7 @@ module function io_get_old_t_final_system(self, param) result(old_t_final)
       end do
       if (is_iostat_end(ierr)) then
          old_t_final = tmpparam%t
+         close(iu)
          return
       end if
 
@@ -468,6 +465,53 @@ module function io_get_token(buffer, ifirst, ilast, ierr) result(token)
       return
    end function io_get_token
 
+   module subroutine io_log_one_message(file, message)
+      !! author: David A. Minton
+      !!
+      !! Writes a single message to a log file
+      implicit none
+      ! Arguments
+      character(len=*), intent(in) :: file   !! Name of file to log
+      character(len=*), intent(in) :: message
+      ! Internals
+      character(STRMAX) :: errmsg
+
+      open(unit=LUN, file=file, status = 'OLD', position = 'APPEND', form = 'FORMATTED', err = 667, iomsg = errmsg)
+      write(LUN, *) trim(adjustl(message)) 
+      close(LUN)
+
+      return
+      667 continue
+      write(*,*) "Error writing  message to log file: " // trim(adjustl(errmsg))
+   end subroutine io_log_one_message
+
+
+   module subroutine io_log_start(param, file, header)
+      !! author: David A. Minton
+      !!
+      !! Checks to see if a log file needs to be created if this is a new run, or appended if this is a restarted run
+      implicit none
+      ! Arguments
+      class(swiftest_parameters), intent(in) :: param  !! Current Swiftest run configuration parameters
+      character(len=*),           intent(in) :: file   !! Name of file to log
+      character(len=*),           intent(in) :: header !! Header to print at top of log file
+      ! Internals
+      character(STRMAX) :: errmsg
+      logical           :: fileExists
+
+      inquire(file=file, exist=fileExists)
+      if (.not.param%lrestart .or. .not.fileExists) then
+         open(unit=LUN, file=file, status="REPLACE", err = 667, iomsg = errmsg)
+         write(LUN, *, err = 667, iomsg = errmsg) trim(adjustl(header))
+      end if
+      close(LUN)
+
+      return
+
+      667 continue
+      write(*,*) "Error writing log file: " // trim(adjustl(errmsg))
+   end subroutine io_log_start
+
 
    module subroutine io_param_reader(self, unit, iotype, v_list, iostat, iomsg) 
       !! author: The Purdue Swiftest Team - David A. Minton, Carlisle A. Wishard, Jennifer L.L. Pouplin, and Jacob R. Elliott
@@ -766,12 +810,22 @@ module subroutine io_param_reader(self, unit, iotype, v_list, iostat, iomsg)
          end associate
 
          select case(trim(adjustl(param%interaction_loops)))
-         case("ADAPTIVE", "FLAT", "TRIANGULAR")
+         case("ADAPTIVE")
+            param%ladaptive_interactions = .true.
+            param%lflatten_interactions = .true.
+         case("TRIANGULAR")
+            param%ladaptive_interactions = .false.
+            param%lflatten_interactions = .false.
+         case("FLAT")
+            param%ladaptive_interactions = .false.
+            param%lflatten_interactions = .true.
          case default
             write(*,*) "Unknown value for parameter INTERACTION_LOOPS: -> ",trim(adjustl(param%interaction_loops))
             write(*,*) "Must be one of the following: TRIANGULAR, FLAT, or ADAPTIVE"
             write(*,*) "Using default value of ADAPTIVE"
             param%interaction_loops = "ADAPTIVE"
+            param%ladaptive_interactions = .true.
+            param%lflatten_interactions = .true.
          end select
 
          iostat = 0
@@ -1092,7 +1146,6 @@ module subroutine io_read_in_body(self, param)
       class(swiftest_body),       intent(inout) :: self   !! Swiftest particle object
       class(swiftest_parameters), intent(inout) :: param !! Current run configuration parameters
       ! Internals
-      integer(I4B), parameter       :: LUN = 7              !! Unit number of input file
       integer(I4B)                  :: iu = LUN
       integer(I4B)                  :: i, nbody
       logical                       :: is_ascii, is_pl
@@ -1157,7 +1210,6 @@ module subroutine io_read_in_cb(self, param)
       class(swiftest_cb),         intent(inout) :: self
       class(swiftest_parameters), intent(inout) :: param
       ! Internals
-      integer(I4B), parameter :: LUN = 7              !! Unit number of input file
       integer(I4B)            :: iu = LUN
       character(len=STRMAX)   :: errmsg
       integer(I4B)            :: ierr, idold
@@ -1225,7 +1277,6 @@ function io_read_encounter(t, id1, id2, Gmass1, Gmass2, radius1, radius2, &
       integer(I4B)         :: ierr
       ! Internals
       logical , save    :: lfirst = .true.
-      integer(I4B), parameter :: lun = 30
       integer(I4B), save    :: iu = lun
 
       if (lfirst) then
@@ -1561,7 +1612,6 @@ module subroutine io_read_in_param(self, param_file_name)
       class(swiftest_parameters),intent(inout) :: self             !! Current run configuration parameters
       character(len=*), intent(in)             :: param_file_name !! Parameter input file name (i.e. param.in)
       ! Internals
-      integer(I4B), parameter :: LUN = 7                 !! Unit number of input file
       integer(I4B)            :: ierr = 0                !! Input error code
       character(STRMAX)       :: errmsg           !! Error message in UDIO procedure
 
@@ -1619,8 +1669,7 @@ module subroutine io_read_particle_info_system(self, param)
       class(swiftest_nbody_system), intent(inout) :: self  !! Swiftest nbody system object
       class(swiftest_parameters),   intent(inout) :: param !! Current run configuration parameters 
       ! Internals
-      integer(I4B), parameter       :: LUN = 22
-      integer(I4B)                  :: i,  id, idx
+      integer(I4B)                  :: i, id, idx
       logical                       :: lmatch  
       character(STRMAX)             :: errmsg
       type(swiftest_particle_info), allocatable :: tmpinfo
@@ -1715,7 +1764,6 @@ module subroutine io_write_discard(self, param)
       class(swiftest_nbody_system), intent(inout) :: self     !! Swiftest system object
       class(swiftest_parameters),   intent(inout) :: param   !! Current run configuration parameters 
       ! Internals
-      integer(I4B), parameter   :: LUN = 40
       integer(I4B)          :: i
       logical, save :: lfirst = .true. 
       real(DP), dimension(:,:), allocatable :: vh
@@ -1800,7 +1848,6 @@ module subroutine io_write_encounter(self, pl, encbody, param)
       class(swiftest_parameters), intent(in) :: param   !! Current run configuration parameters 
       ! Internals
       logical , save          :: lfirst = .true.
-      integer(I4B), parameter :: LUN = 30
       integer(I4B)            :: k, ierr
       character(len=STRMAX)   :: errmsg
 
diff --git a/src/kick/kick.f90 b/src/kick/kick.f90
index 0e90e73ee..2626c6d34 100644
--- a/src/kick/kick.f90
+++ b/src/kick/kick.f90
@@ -17,9 +17,7 @@ module subroutine kick_getacch_int_pl(self, param)
       type(interaction_timer), save :: itimer
       logical, save :: lfirst
 
-      if (lfirst) then
-         call itimer%reset(param)
-      end if
+      if (lfirst) call itimer%reset(param)
       if (param%lflatten_interactions) then
          call kick_getacch_int_all_flat_pl(self%nbody, self%nplpl, self%k_plpl, self%xh, self%Gmass, self%radius, self%ah)
       else
diff --git a/src/modules/fraggle_classes.f90 b/src/modules/fraggle_classes.f90
index 63440383f..7fefe652b 100644
--- a/src/modules/fraggle_classes.f90
+++ b/src/modules/fraggle_classes.f90
@@ -113,12 +113,6 @@ module subroutine fraggle_io_log_generate(frag)
          class(fraggle_fragments),   intent(in) :: frag
       end subroutine fraggle_io_log_generate
 
-      module subroutine fraggle_io_log_one_message(message)
-         implicit none
-         character(len=*), intent(in) :: message
-         character(STRMAX) :: errmsg
-      end subroutine fraggle_io_log_one_message
-
       module subroutine fraggle_io_log_pl(pl, param)
          implicit none
          class(swiftest_pl),         intent(in) :: pl    !! Swiftest massive body object (only the new bodies generated in a collision)
@@ -131,11 +125,6 @@ module subroutine fraggle_io_log_regime(colliders, frag)
          class(fraggle_fragments),   intent(in) :: frag
       end subroutine fraggle_io_log_regime
 
-      module subroutine fraggle_io_log_start(param)
-         implicit none
-         class(swiftest_parameters), intent(in) :: param
-      end subroutine fraggle_io_log_start
-
       !> The following interfaces are placeholders intended to satisfy the required abstract methods given by the parent class
       module subroutine fraggle_placeholder_accel(self, system, param, t, lbeg)
          use swiftest_classes, only : swiftest_nbody_system, swiftest_parameters
diff --git a/src/modules/swiftest_classes.f90 b/src/modules/swiftest_classes.f90
index 89c5ef238..46cf56369 100644
--- a/src/modules/swiftest_classes.f90
+++ b/src/modules/swiftest_classes.f90
@@ -123,6 +123,9 @@ module swiftest_classes
       real(DP)             :: inv_c2         = -1.0_DP            !! Inverse speed of light squared in the system units
       character(STRMAX)    :: energy_out     = ""                 !! Name of output energy and momentum report file
       character(NAMELEN)   :: interaction_loops = "ADAPTIVE"      !! Method used to compute interaction loops. Options are "TRIANGULAR", "FLAT", or "ADAPTIVE" 
+      ! The following are used internally, and are not set by the user, but instead are determined by the input value of INTERACTION_LOOPS
+      logical :: lflatten_interactions = .false. !! Use the flattened upper triangular matrix for pl-pl interaction loops
+      logical :: ladaptive_interactions = .false. !! Adaptive interaction loop is turned on
 
       ! Logical flags to turn on or off various features of the code
       logical :: lrhill_present = .false. !! Hill radii are given as an input rather than calculated by the code (can be used to inflate close encounter regions manually)
@@ -133,7 +136,6 @@ module swiftest_classes
       logical :: loblatecb      = .false. !! Calculate acceleration from oblate central body (automatically turns true if nonzero J2 is input)
       logical :: lrotation      = .false. !! Include rotation states of big bodies
       logical :: ltides         = .false. !! Include tidal dissipation 
-      logical :: lflatten_interactions = .false. !! Use the flattened upper triangular matrix for pl-pl interactions (turning this on improves the speed but uses more memory)
 
       ! Initial values to pass to the energy report subroutine (usually only used in the case of a restart, otherwise these will be updated with initial conditions values)
       real(DP)                  :: Eorbit_orig = 0.0_DP   !! Initial orbital energy
@@ -707,6 +709,19 @@ module function io_get_token(buffer, ifirst, ilast, ierr) result(token)
          character(len=:), allocatable   :: token          !! Returned token string
       end function io_get_token
 
+      module subroutine io_log_one_message(file, message)
+         implicit none
+         character(len=*), intent(in) :: file   !! Name of file to log
+         character(len=*), intent(in) :: message
+      end subroutine io_log_one_message
+   
+      module subroutine io_log_start(param, file, header)
+         implicit none
+         class(swiftest_parameters), intent(in) :: param  !! Current Swiftest run configuration parameters
+         character(len=*),           intent(in) :: file   !! Name of file to log
+         character(len=*),           intent(in) :: header !! Header to print at top of log file
+      end subroutine io_log_start
+
       module subroutine io_param_reader(self, unit, iotype, v_list, iostat, iomsg) 
          implicit none
          class(swiftest_parameters), intent(inout) :: self       !! Collection of parameters
diff --git a/src/modules/swiftest_globals.f90 b/src/modules/swiftest_globals.f90
index 1f9c6028c..b7fe1a0db 100644
--- a/src/modules/swiftest_globals.f90
+++ b/src/modules/swiftest_globals.f90
@@ -113,9 +113,9 @@ module swiftest_globals
 
    !> Standard file names
    integer(I4B), parameter :: NDUMPFILES = 2
-   character(*), dimension(2), parameter :: DUMP_CB_FILE    = ['dump_cb1.bin',    'dump_cb2.bin'   ]
-   character(*), dimension(2), parameter :: DUMP_PL_FILE    = ['dump_pl1.bin',    'dump_pl2.bin'   ]
-   character(*), dimension(2), parameter :: DUMP_TP_FILE    = ['dump_tp1.bin',    'dump_tp2.bin'   ]
+   character(*), dimension(2), parameter :: DUMP_CB_FILE    = ['dump_cb1.bin',    'dump_cb2.bin'  ]
+   character(*), dimension(2), parameter :: DUMP_PL_FILE    = ['dump_pl1.bin',    'dump_pl2.bin'  ]
+   character(*), dimension(2), parameter :: DUMP_TP_FILE    = ['dump_tp1.bin',    'dump_tp2.bin'  ]
    character(*), dimension(2), parameter :: DUMP_PARAM_FILE = ['dump_param1.in',  'dump_param2.in']
 
    !> Default file names that can be changed by the user in the parameters file
@@ -126,6 +126,7 @@ module swiftest_globals
    integer(I4B), parameter :: BINUNIT          = 20 !! File unit number for the binary output file
    character(*), parameter :: PARTICLE_OUTFILE = 'particle.dat'
    integer(I4B), parameter :: PARTICLEUNIT     = 44 !! File unit number for the binary particle info output file
+   integer(I4B), parameter :: LUN              = 42 !! File unit number for files that are opened and closed within a single subroutine call, and therefore should not collide
 
    !> Miscellaneous constants:
    integer(I4B), parameter :: NDIM   = 3                  !! Number of dimensions in our reality
diff --git a/src/modules/walltime_classes.f90 b/src/modules/walltime_classes.f90
index 76600660d..c353328d8 100644
--- a/src/modules/walltime_classes.f90
+++ b/src/modules/walltime_classes.f90
@@ -27,11 +27,25 @@ module walltime_classes
       integer(I4B)           :: step_counter
       integer(I8B)           :: count_previous
       character(len=NAMELEN) :: current_style
+      logical                :: lflatten_interaction_old
    contains
-
+      procedure :: reset  => walltime_interaction_reset  !! Resets the interaction loop timer, and saves the current value of the array flatten parameter
    end type interaction_timer
 
    interface
+      module subroutine walltime_interaction_reset(self, param)
+         use swiftest_classes, only : swiftest_parameters
+         implicit none
+         class(interaction_timer),   intent(inout) :: self  !! Walltimer object
+         class(swiftest_parameters), intent(inout) :: param !! Current run configuration parameters
+      end subroutine walltime_interaction_reset 
+
+      module subroutine walltime_interaction_io_log_start(param)
+         use swiftest_classes, only : swiftest_parameters
+         implicit none
+         class(swiftest_parameters), intent(in) :: param
+      end subroutine walltime_interaction_io_log_start
+
       module subroutine walltime_finish(self, nsubsteps, message, param)
          use swiftest_classes, only : swiftest_parameters
          implicit none
@@ -58,6 +72,23 @@ end subroutine walltime_start
 
    contains
 
+      module subroutine walltime_interaction_reset(self, param)
+         !! author: David A. Minton
+         !!
+         !! Resets the interaction loop timer, and saves the current value of the array flatten parameter
+         use swiftest_classes, only : swiftest_parameters
+         implicit none
+         ! Arguments
+         class(interaction_timer),   intent(inout) :: self  !! Walltimer object
+         class(swiftest_parameters), intent(inout) :: param !! Current run configuration parameters
+
+         self%lflatten_interaction_old = param%lflatten_interactions
+         call walltime_reset(self, param)
+
+         return
+      end subroutine walltime_interaction_reset 
+
+
       module subroutine walltime_finish(self, nsubsteps, message, param)
          !! author: David A. Minton
          !!
diff --git a/src/rmvs/rmvs_io.f90 b/src/rmvs/rmvs_io.f90
index b85ce2202..51f077852 100644
--- a/src/rmvs/rmvs_io.f90
+++ b/src/rmvs/rmvs_io.f90
@@ -19,7 +19,6 @@ module subroutine rmvs_io_write_encounter(t, id1, id2, Gmass1, Gmass2, radius1,
       character(*),           intent(in) :: enc_out
       ! Internals
       logical , save    :: lfirst = .true.
-      integer(I4B), parameter :: LUN = 30
       integer(I4B)        :: ierr
 
       if (enc_out == "") return
diff --git a/src/symba/symba_collision.f90 b/src/symba/symba_collision.f90
index 864eaa723..baa51485a 100644
--- a/src/symba/symba_collision.f90
+++ b/src/symba/symba_collision.f90
@@ -28,7 +28,7 @@ module function symba_collision_casedisruption(system, param, colliders, frag)
          message = "Supercatastrophic disruption between"
       end select
       call symba_collision_collider_message(system%pl, colliders%idx, message)
-      call fraggle_io_log_one_message(message)
+      call io_log_one_message(FRAGGLE_LOG_OUT, message)
 
       ! Collisional fragments will be uniformly distributed around the pre-impact barycenter
       call frag%set_mass_dist(colliders, param)
@@ -37,7 +37,7 @@ module function symba_collision_casedisruption(system, param, colliders, frag)
       call frag%generate_fragments(colliders, system, param, lfailure)
 
       if (lfailure) then
-         call fraggle_io_log_one_message("No fragment solution found, so treat as a pure hit-and-run")
+         call io_log_one_message(FRAGGLE_LOG_OUT, "No fragment solution found, so treat as a pure hit-and-run")
          status = ACTIVE 
          nfrag = 0
          select type(pl => system%pl)
@@ -50,7 +50,7 @@ module function symba_collision_casedisruption(system, param, colliders, frag)
          ! Populate the list of new bodies
          nfrag = frag%nbody
          write(message, *) nfrag
-         call fraggle_io_log_one_message("Generating " // trim(adjustl(message)) // " fragments")
+         call io_log_one_message(FRAGGLE_LOG_OUT, "Generating " // trim(adjustl(message)) // " fragments")
          select case(frag%regime)
          case(COLLRESOLVE_REGIME_DISRUPTION)
             status = DISRUPTION
@@ -87,7 +87,7 @@ module function symba_collision_casehitandrun(system, param, colliders, frag)  r
 
       message = "Hit and run between"
       call symba_collision_collider_message(system%pl, colliders%idx, message)
-      call fraggle_io_log_one_message(trim(adjustl(message)))
+      call io_log_one_message(FRAGGLE_LOG_OUT, trim(adjustl(message)))
 
       if (colliders%mass(1) > colliders%mass(2)) then
          jtarg = 1
@@ -98,7 +98,7 @@ module function symba_collision_casehitandrun(system, param, colliders, frag)  r
       end if
 
       if (frag%mass_dist(2) > 0.9_DP * colliders%mass(jproj)) then ! Pure hit and run, so we'll just keep the two bodies untouched
-         call fraggle_io_log_one_message("Pure hit and run. No new fragments generated.")
+         call io_log_one_message(FRAGGLE_LOG_OUT, "Pure hit and run. No new fragments generated.")
          nfrag = 0
          lpure = .true.
       else ! Imperfect hit and run, so we'll keep the largest body and destroy the other
@@ -109,12 +109,12 @@ module function symba_collision_casehitandrun(system, param, colliders, frag)  r
          call frag%generate_fragments(colliders, system, param, lpure)
 
          if (lpure) then
-            call fraggle_io_log_one_message("Should have been a pure hit and run instead")
+            call io_log_one_message(FRAGGLE_LOG_OUT, "Should have been a pure hit and run instead")
             nfrag = 0
          else
             nfrag = frag%nbody
             write(message, *) nfrag
-            call fraggle_io_log_one_message("Generating " // trim(adjustl(message)) // " fragments")
+            call io_log_one_message(FRAGGLE_LOG_OUT, "Generating " // trim(adjustl(message)) // " fragments")
          end if
       end if
       if (lpure) then ! Reset these bodies back to being active so that nothing further is done to them
@@ -164,7 +164,7 @@ module function symba_collision_casemerge(system, param, colliders, frag)  resul
 
       message = "Merging"
       call symba_collision_collider_message(system%pl, colliders%idx, message)
-      call fraggle_io_log_one_message(message)
+      call io_log_one_message(FRAGGLE_LOG_OUT, message)
 
       select type(pl => system%pl)
       class is (symba_pl)
@@ -358,7 +358,7 @@ module function symba_collision_check_encounter(self, system, param, t, dt, irec
                      write(message, *) "Particle " // trim(adjustl(tp%info(j)%name)) // " ("  // trim(adjustl(idstrj)) // ")" &
                              //  " collided with massive body " // trim(adjustl(pl%info(i)%name)) // " (" // trim(adjustl(idstri)) // ")" &
                              //  " at t = " // trim(adjustl(timestr))
-                     call fraggle_io_log_one_message(message)
+                     call io_log_one_message(FRAGGLE_LOG_OUT, message)
                   end if
                end if
             end do
@@ -984,10 +984,10 @@ module subroutine symba_collision_resolve_plplenc(self, system, param, t, dt, ir
 
                do
                   write(timestr,*) t
-                  call fraggle_io_log_one_message("")
-                  call fraggle_io_log_one_message("***********************************************************************************************************************")
-                  call fraggle_io_log_one_message("Collision between massive bodies detected at time t = " // trim(adjustl(timestr)))
-                  call fraggle_io_log_one_message("***********************************************************************************************************************")
+                  call io_log_one_message(FRAGGLE_LOG_OUT, "")
+                  call io_log_one_message(FRAGGLE_LOG_OUT, "***********************************************************************************************************************")
+                  call io_log_one_message(FRAGGLE_LOG_OUT, "Collision between massive bodies detected at time t = " // trim(adjustl(timestr)))
+                  call io_log_one_message(FRAGGLE_LOG_OUT, "***********************************************************************************************************************")
                   allocate(tmp_param, source=param)
                   tmp_param%t = t
                   if (param%lfragmentation) then
diff --git a/src/symba/symba_discard.f90 b/src/symba/symba_discard.f90
index 704d11f85..592b146b8 100644
--- a/src/symba/symba_discard.f90
+++ b/src/symba/symba_discard.f90
@@ -37,11 +37,11 @@ subroutine symba_discard_cb_pl(pl, system, param)
                   write(idstr, *) pl%id(i)
                   write(timestr, *) param%t
                   write(message, *) trim(adjustl(pl%info(i)%name)) // " (" // trim(adjustl(idstr)) // ")" // " too far from the central body at t = " // trim(adjustl(timestr))
-                  call fraggle_io_log_one_message("")
-                  call fraggle_io_log_one_message("***********************************************************************************************************************")
-                  call fraggle_io_log_one_message(message)
-                  call fraggle_io_log_one_message("***********************************************************************************************************************")
-                  call fraggle_io_log_one_message("")
+                  call io_log_one_message(FRAGGLE_LOG_OUT, "")
+                  call io_log_one_message(FRAGGLE_LOG_OUT, "***********************************************************************************************************************")
+                  call io_log_one_message(FRAGGLE_LOG_OUT, message)
+                  call io_log_one_message(FRAGGLE_LOG_OUT, "***********************************************************************************************************************")
+                  call io_log_one_message(FRAGGLE_LOG_OUT, "")
                   call pl%info(i)%set_value(status="DISCARDED_RMAX", discard_time=param%t, discard_xh=pl%xh(:,i), discard_vh=pl%vh(:,i))
                else if ((param%rmin >= 0.0_DP) .and. (rh2 < rmin2)) then
                   pl%ldiscard(i) = .true.
@@ -50,11 +50,11 @@ subroutine symba_discard_cb_pl(pl, system, param)
                   write(idstr, *) pl%id(i)
                   write(timestr, *) param%t
                   write(message, *) trim(adjustl(pl%info(i)%name)) // " ("  // trim(adjustl(idstr)) // ")" // " too close to the central body at t = " // trim(adjustl(timestr))
-                  call fraggle_io_log_one_message("")
-                  call fraggle_io_log_one_message("***********************************************************************************************************************")
-                  call fraggle_io_log_one_message(message)
-                  call fraggle_io_log_one_message("***********************************************************************************************************************")
-                  call fraggle_io_log_one_message("")
+                  call io_log_one_message(FRAGGLE_LOG_OUT, "")
+                  call io_log_one_message(FRAGGLE_LOG_OUT, "***********************************************************************************************************************")
+                  call io_log_one_message(FRAGGLE_LOG_OUT, message)
+                  call io_log_one_message(FRAGGLE_LOG_OUT, "***********************************************************************************************************************")
+                  call io_log_one_message(FRAGGLE_LOG_OUT, "")
                   call pl%info(i)%set_value(status="DISCARDED_RMIN", discard_time=param%t, discard_xh=pl%xh(:,i), discard_vh=pl%vh(:,i), discard_body_id=cb%id)
                else if (param%rmaxu >= 0.0_DP) then
                   rb2 = dot_product(pl%xb(:,i), pl%xb(:,i))
@@ -67,11 +67,11 @@ subroutine symba_discard_cb_pl(pl, system, param)
                      write(idstr, *) pl%id(i)
                      write(timestr, *) param%t
                      write(message, *) trim(adjustl(pl%info(i)%name)) // " (" // trim(adjustl(idstr)) // ")" // " is unbound and too far from barycenter at t = " // trim(adjustl(timestr))
-                     call fraggle_io_log_one_message("")
-                     call fraggle_io_log_one_message("***********************************************************************************************************************")
-                     call fraggle_io_log_one_message(message)
-                     call fraggle_io_log_one_message("***********************************************************************************************************************")
-                     call fraggle_io_log_one_message("")
+                     call io_log_one_message(FRAGGLE_LOG_OUT, "")
+                     call io_log_one_message(FRAGGLE_LOG_OUT, "***********************************************************************************************************************")
+                     call io_log_one_message(FRAGGLE_LOG_OUT, message)
+                     call io_log_one_message(FRAGGLE_LOG_OUT, "***********************************************************************************************************************")
+                     call io_log_one_message(FRAGGLE_LOG_OUT, "")
                      call pl%info(i)%set_value(status="DISCARDED_RMAXU", discard_time=param%t, discard_xh=pl%xh(:,i), discard_vh=pl%vh(:,i))
                   end if
                end if
diff --git a/src/symba/symba_io.f90 b/src/symba/symba_io.f90
index 2e5e87941..3f481d9b4 100644
--- a/src/symba/symba_io.f90
+++ b/src/symba/symba_io.f90
@@ -96,7 +96,7 @@ module subroutine symba_io_param_reader(self, unit, iotype, v_list, iostat, ioms
          end if
 
          ! All reporting of collision information in SyMBA (including mergers) is now recorded in the Fraggle logfile
-         call fraggle_io_log_start(param)
+         call io_log_start(param, FRAGGLE_LOG_OUT, "Fraggle logfile")
 
          ! Call the base method (which also prints the contents to screen)
          call io_param_reader(param, unit, iotype, v_list, iostat, iomsg) 
@@ -155,7 +155,6 @@ module subroutine symba_io_write_discard(self, param)
       class(symba_nbody_system),  intent(inout) :: self  !! SyMBA nbody system object
       class(swiftest_parameters), intent(inout) :: param !! Current run configuration parameters 
       ! Internals
-      integer(I4B), parameter   :: LUN = 40
       integer(I4B)          :: iadd, isub, j, nsub, nadd
       logical, save :: lfirst = .true. 
       real(DP), dimension(:,:), allocatable :: vh