You can divide all fish into three categories of where they stay in the tank.
Top, middle, and bottom. you can work that out on any fish even if you havent seen one before.
Just check their mouths. E.G.; Gouramis mouths point up, barbs mouths are central, and ALMOST all cichlids and all catfish point down.
from that, you can work out what fish will live in the same tank. Overpopulate one area and you get competition and fighting.
If your filter pipe is large enough to swallow a gourami, change the fliter pipe end.
Small cichlids will cope well in most tanks. What used to called apistogramma ramirizi are very nice fish. I'm pretty sure they got reclassified but you should find them as "RAM" cichlids. There are more types of dwarf american cichlids about nowadays, but I have no experience of them. I've bred ram cichlids, as well as the much easier firemouths, and the family friends known as oscars =D> . But firemouths tend to mess the tank bottom up so plants become difficult. Oscars destroy EVERYTHING when they decide to breed
Another help is that cichlids come from 2 main places, south america, and africa. Mixing them is bad news, apart from the fact their water requirements are quite different .
"I need more tanks" :lol: :lol: :lol: :lol: :lol: :lol: :lol: :lol: :lol: :lol:
Oh dear, youre hooked (pun intended).
My 1 became 2 and then 5 and then 15 and then a shop full of 150. Theres no turning back.
Now then, TURTLES...... They are amusing, but actually quite dangerous. They are incredibly messy eaters, and they all carry salmonella and many other bacterial diseases. If you have small children likely to touch them when unsupervised DO NOT BUY. If you touch them at any time (including water changes) you must wash your hands well immediately.
They will eat small fish. As they get bigger, they can easily bite an unwary handler, and that should be a hospital visit.