I have a new 8 gallon tank. The fish in it are two platties and a corydoras catfish, which are all getting along rather well. I have four nicely grouped plants in it and some slightly larger rocks that are for the catfish to hide behind should he care to. Generally they seem happy, their colour is good. I haven't owned fish in a while though and I seem to find differing views on some things. 1. My platties seem to be stress free except moments when something startles them. However I'm told that the male is likely to harass the female, and yet I haven't seen any signs of this. Should I nevertheless think of getting another female? 2. The amount of fish per gallon seems to vary as well. I'm not sure if adding another fish, even a small one like a platty is actually a good idea.