I have 2 Firemouths in a 120 cm tank that I have raised from 2 cm, now at least 6 cm. The Firemouth is an extremely hardy fish. Recently the male tried to eat a cichlid pellet too big for it to swallow and was lying on the bottom of the tank with the pellet stuck in his mouth (looking very dead). I pulled it out and held it while my mate removed the pellet with a pin (very carefully). Few days later the fish is back to normal (incredible). Great fish!
I have 2 firemouths and I had them in a tank with Jack Dempsey's and African Cichlids. They held their own despite the flurry of activity and 'territory issues'. I now have just South American cichlids and angelfish, green severum, Jack's and oscars. The adults are the Jack's, the Firemouths and the angelfish. Still excellent companions, no matter what the contents of the tank. They do well and are hearty fish.
I have several firemouths and they are a joy. I came home one nigh to find they had hatched several hundred fry in hiding. They are excellent parents but do not get to vicious when defending their babies. IMPO, these cichlids are great for any level of cichlid keeper and won't be a disappointment with their beautiful colors and people-friendly disposition.
I have had firemouths in the past and they were wonderful. However, beware if he/she is to be the largest or most aggressive fish to be placed in your peaceful tank. I thought my juvenile 10 cm Jurupari would keep the 8 cm firemouth in check, but no way. The firemouth displayed aggression that I have never seen from the species in my 10 years of cichlid keeping. I have always had 15 cm or larger Severums, Oscars and other smaller more aggressive Salvini's and Convicts with firemouths and with that company had no choice but to behave. One of my favorite cichlids, but be careful, give it tough company or no company.
I have a pair of Firemouths, a Blue Ram and a Bolivian Ram in a 110 L tank. I noticed the Firemouths were guarding about 350 babies! The Blue and Bolivian Rams tried to eat the babies and daddy flared his colorful gills as if to say, back away from my children! Anyway, I suggest any aquariust who wants a peaceful, easy to breed Central American Cichlid then get Firemouths!
Firemouths are gorgeous fish that I have found to be fairly hardy. Males have more vibrant colors along their throat, giving them the name firemouth, while female colors are quite a bit duller, but closer to an actual red. They can be mildly aggressive to other fish, but are generally peaceful. Avoid mixing them with angels, as they will almost certainly attack them.
The one defining characteristic in them is that they have such intense and varied personalities. This can include docile, timid, outgoing and alpha male. The one female I have, Belle, is docile and lives happily with danios, rasboras, rams, a cherry barb, several small cory cats, and a rummy nose. She can be rather shy, but defends her two separate territories by swimming quickly at other fish, scattering them, although I have never seen them actually touch. An odd thing is that as docile as she is, she is firmly established as a kind of 'top of the tank' leader. My gold gourami sometimes harasses my pearl and blue gouramis, but Belle will lunge at her and scare her off, leaving the pearl gourami and blue gourami safe.
Firemouths prefer planted tanks, and tend to stay in the lower regions. Most Firemouths will eat other small fish, unlike the one I have, and will definitely swallow up cardinal and neon tetras. Make sure they have a place to hide, as they need some kind of hideaway or they can get rather stressed. Just be wary of their wild card personalities when buying.
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