diff --git a/src/Utility/Particle_Tracking/particle.bp b/src/Utility/Particle_Tracking/particle.bp
index 00694aa3d..6f5d97d67 100644
--- a/src/Utility/Particle_Tracking/particle.bp
+++ b/src/Utility/Particle_Tracking/particle.bp
@@ -14,5 +14,5 @@ Input for ptrack*
 1  0                  !ibuoy,iwind
 20.0                  !pbeach
 !start of biofouling paramaters, needed only if ibiofoul=1
- !bio_R0,bio_BT0,bio_BR,bio_den0
+1.e-5 0. 1.e-4 0.1 1.e-3   !bio_R0,bio_BT0,bio_BR,bio_den0 (\rho_0),bio_den_biolayer (\rho_D)
 
diff --git a/src/Utility/Particle_Tracking/ptrack4.f90 b/src/Utility/Particle_Tracking/ptrack4.f90
index 5c8ab617c..9f288abbd 100755
--- a/src/Utility/Particle_Tracking/ptrack4.f90
+++ b/src/Utility/Particle_Tracking/ptrack4.f90
@@ -253,7 +253,7 @@ program ptrack
         read(95,*) !comment line
         !init plastic radius (m),init thickness of fouling layer (m), 
         !bio growth (m/day),init density of plastic particle (kg/m^3),
-        ! density of biofoul layer (kg/m^3)
+        !density of biofoul layer (kg/m^3)
         read(95,*)bio_R0,bio_BT0,bio_BR,bio_den0,bio_den_biolayer
       endif !ibiofoul/