A pair of dwarves would work, most people try to have fish that spend time at different levels, like bottom fish, mid dwellers and top swimming fish. Cories are nice bottomw fish, as are khuli loaches, for top swimmers marble hatchet fish are neat. It really depends on what fis YOU like. Take a walk through your local fish stores and see what catches your eye, research it and see if they'd be a good fit with the gouramis. It takes planning to have a nice setup. Are you working on your cycle right now?
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