I found someone on CL giving away some dwarf puffers they bought without doing any research and since I've wanted to do a dwarf puffer tank for a while and have some extra/empty tanks, I figure now is as good a time as any. I have three tanks I can use. I have a 5g flat back hex, a 10g and a 20gL. I know I can realistically only fit one puffer in either the 5g or 10g. But what about the 20gL? The guy said that he's pretty sure they're all females.