alright thanks heaps i am pretty sure the one being left out is the male they do swim together but after a while the slimmer one tends to wonder around the bottom of the tank alone and not join in with the other 3 fatter fish but after a while he will rejoin then stop. is there anyway to make the presumed male feel more apart of the group as the tank only has these 4 fish at the moment if i bu 4 more of these fish do you think that would be wise and if so would i get 3 females and 1 male or what would you suggest? you buy them in groups of 4
another question is how would you determine if a female is pregnant due to them already being larger and have a more fuller shape to them?