29 gallon... how frequent cories?

I have a 29 gallon with a single convict right now. I want to make a payment cories. How many are reccommended?

Also, I like black skirt tetras, but im thinking with the convict that wont work out. what do you come up with? Is there any kind of schooling fish that would work out, or is it best to just stick to the convict?
Answers:    none really, convicts are callous, mean fish, and their "lair" is on the bottom where the cories would be. in a 29 you should simply add another convict and let 'em breed, convicts should only be near other, bigger agressive fish that can fight back, most are going to be too big for a 29, you could try a firemouth though, that should work. If you do add something else, since the convict is already surrounded by there and probably has its territory established, remove him/her, sort out the tank and reintroduce the new fish and the convict at the same time, this can minister to reduce the agresivness but like I said, convicts are killers
3-4 will be fine. and hiding places please..

add on some chichilids... they are good with it.
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