Unless you already have some the same size do not buy 3. Three of any cichlid is begging for touble. A pair will form and they will either kill the other one or make it's life miserable.
yea i was thinking on getting the 5 of em but I dont have anywhere to put them until the summer
well I have a 29 and a 33
but why wouldnt three work these are a social type of cichlid are they not?
By cull I mean take them out of the tank, separate them, etc, not necessarily kill them.
I wouldn't suggest going for 3 as if/when two of them pair up you'll be left with one by itself who is likely to get picked on. In a larger group at least you'll have a few more to spread the aggression, and a better chance of getting a pair. Both your tanks are too small for them at 5", regardless of weather you get 3 or 5.