Prime conditioner

but if I am not mistaken one capfull on the smallest bottle is not the same volume as one capfull on the biggest bottle..

I believe that is the problem...

I don't use Prime so I can't comment on the specific directions but I thought this is what was confusing some people.
I only purchase the 250ml version, thats the biggest in the stores here, but thats why its always a good idea to read the directions on the bottle, or on any product for that matter....:)
 
AquariaCentral.com