diff --git a/init_velocity.f90 b/init_velocity.f90
index 1a5cbf7..96e0a19 100644
--- a/init_velocity.f90
+++ b/init_velocity.f90
@@ -266,8 +266,10 @@ subroutine init_velocity
         do i = 1,nx+2
 
            n_shell = nint(sqrt(real(akx(i)**2 + aky(k)**2 + akz(j)**2, 4)))
-           if (n_shell .gt. 0 .and. n_shell .le. kmax .and. e_spec(n_shell) .gt. zip) then
+           if (n_shell .gt. 0 .and. n_shell .le. kmax ) then
+              if (e_spec(n_shell) .gt. zip) then
               fields(i,j,k,1:3) = fields(i,j,k,1:3) * sqrt(e_spec1(n_shell)/e_spec(n_shell))
+              endif
            else
               fields(i,j,k,1:3) = zip
            end if