You have remember that fish are territorial and each species has a different bio load. The inch per gallon does not always apply I would recommend going with community fish allowing them space. The German blue ram and neon tetras for example. I would stay away from cichlids as they are very territorial and can outgrow their space. Other species may include the red fin tetra, platys, dwarf gouramis. A good ratio of males to females is crucial too. For example, if you want three male dgs then you need at least two females. Bottom line, I would go community and do your research as far as size, territory, and temperament. You want your buddies to be happy and comfortable.
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