Maybe a stupid question

I think 20 gal is a bit on the small side for cichlids. Even dwarf cichlids like apistos or rams. Even though their body size is small, they (like almost all cichlids) can get aggressive and are active so need their space.

I think dwarf species of gouramis would be nice. They're very colorful. That or some pretty tetras. I have bloodfin tetras and their fins are a beautiful, vibrant deep red. Guppies can also be very colorful, but you have to watch your genders or they'll breed like mad. All of the above are omnivores.

One thing to watch out for with tetras is proper school size. If you have too few, they have a tendency to get aggressive amongst themselves.
 
Thank you very much.....Is it true that I cannot keep 2 dwarf gourami's in the tank? Does it have to be 1 or 3 or more? I would like to have a blue and a red one and then 2 small schools of fish.
 
I think the male gouramis will get aggressive with each other. But I think distinguishing male from female is pretty difficult, so most people just stick with the 1 gourami. I have no personal experience with gouramis, so perhaps someone else can shed light.

You're more than welcome. That's why we're here! I'm just glad you're asking questions BEFORE buying :)
 
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