This is a discussion on Can these two mix? within the Cichlids forums, part of the Freshwater and Tropical Fish category; -->
Can fire mouths and angel fish ( that have been brought up in hard water) be kept together
You don't mention the tank size; if it is large enough, yes, these two fish can co-exist.
Angelfish (Pterophyllum scalare) should be in a small group, 4 being absolute minimum but better with 5 or 6. This requires a 4-foot tank, say 55g minimum.
Firemouth is not strictly speaking a shoaling fish (as angelfish are) but it does naturally live in groups with each male defending a distinct territory. It should be kept either singly or as a pair (male/female) in a 3-foot (40+g) tank, or in a small group of again 4-6 in no less than a 4-foot 55g.
You don't say how many of each nor the tank size. One Firemouth would likely be OK with the angelfish group in a 55g, but for any more a larger tank, 90g or above.
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