Dealing with an aggressive cichlid

[emeraldh]

Hey everyone, I've got a bit of a situation with my 55 gallon tank. I've got a mix of 13 haps and peacocks, and one of my cichlids was getting pretty roughed up - nipped fins and bruises all over. I'd add Melafix to help him recover, but it was a recurring thing. Then, after about a week, that same fish ended up dead. I'm pretty sure it was due to aggression from the dominant cichlid in my tank.

I've since removed that aggressive cichlid and isolated him in another tank. I've tried rearranging decorations to reset territories and even added more fish to disperse the aggression, but for some reason, this one fish just had it out for the one that got killed. The dominant fish is about 4-5 inches, while most of the others are around 3-4 inches, with a few exceptions that are similar in size to the dominant one. I'm thinking his size might be the reason for the extra aggression.

I've had him isolated for about a week now, and I really don't want him to hurt any more of my fish. Has anyone got any ideas on how to reduce aggression or any recommendations that might help me out? I've attached some pics of the isolated fish if anyone wants to take a look.

[rustyfox]

I've had a similar experience with temporarily removing aggressive fish, only to see them revert to their old ways once reintroduced to the main tank. One of my fluxeonblood peacocks spent over a month in isolation, but as soon as I put him back, he went right back to being aggressive. Ultimately, I had to rehome him at the petstore just last week.

[emeraldh]

Thanks for sharing your experience, I really appreciate it.

[earthie_9]

African cichlids can be quite the handful, I've been there myself. I had a dominant male yellow lab that just wouldn't calm down - he'd harass even the larger fish in the tank, like my female livingstonii and blue zebra. I recall one incident where he killed a female peacock just because she wouldn't spawn with him. Needless to say, the tank's been much more peaceful since I traded him in.

Given your situation, I think you have two options: rehome your aggressive male or consider upgrading your tank and adding more fish to the mix. This might help distribute the aggression more evenly and create a more balanced environment.

On a side note, most haps do tend to outgrow a 55-gallon tank, but I'm guilty of ignoring that rule myself. I've got a young EB ahli in my 55, and he's still growing, so I'm keeping a close eye on him.

[emeraldh]

Thanks for the insight, I'll definitely keep that in mind. I'm planning on reintroducing the dominant cichlid back into the tank soon, if his aggression persists I'll likely rehome him. A friend of mine has a tank with larger cichlids, but they're Mbunas, I'm not sure if my fish would mesh well with his, I'll have to see what he thinks about it.