diff --git a/columnphysics/icepack_therm_vertical.F90 b/columnphysics/icepack_therm_vertical.F90
index 2d0c20cea..bca098ea6 100644
--- a/columnphysics/icepack_therm_vertical.F90
+++ b/columnphysics/icepack_therm_vertical.F90
@@ -638,7 +638,7 @@ subroutine frzmlt_bottom_lateral (dt,       ncat,     &
       ! FYI: fside is not yet correct for fsd, may need to adjust fbot further
       !-----------------------------------------------------------------
 
-         xtmp = frzmlt/(fbot + fside + puny)
+         xtmp = frzmlt/(fbot + fside - puny)
          xtmp = min(xtmp, c1)
          fbot  = fbot  * xtmp
          rside = rside * xtmp