Can a convict live in a 20 gallon tank?

Its your tank you can place whatever you want in there, just be mindful some fish do not fair well in cramped quarters, a 20gal high will suffice but will the fish be happy, you can also put a breeding pair in that tank, they will breed and when there ready they will breed again and kill anything in the tank even their offspring..
 
Are you still dealing with fish mysteriously dying? If so...

I've also read a few of your previous threads and maybe you should take a step back before you try to setup more tanks. Figure out what's going on with your current ones if all your fish are dying as your signature says...

While something MAY work, there are much better stocking options than convicts for a 20H. I'd advise that you look at getting more than just the minimum in this hobby. It goes a long way in keeping healthier fish.
 
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