I have had a fully grown male rainbow cichlid for a year now and he's an incredibly aggressive fish. I have had Jewels, convicts, keyholes and firemouths and yet my male rainbow is FAR more aggressive than anything else I have had. He goes for my hand every time I put my hand in the tank to move decor around, clean the tank or put back uprooted plants. For a long time I thought it was kind of neat but it's becoming a real pain. Even though when he bites me, it's not painful, it's still a fright because he often sneaks up on me. I always pull my hand away quickly and one time actually scraped it pretty hard on the plastic framing. Last week I got soaked pulling my hand out super fast to avoid a bite. I'm not exaggerating. I needed a towel. He uproots plants a lot so I'm usually sticking my hand in the tank once every couple of days and I'm no longer comfortable doing so. I still love the fish and I'm just venting, but something that I once found charming has become a real pain in the derrierre and I just needed to get it off my chest.