I have a jewel cichlid, and its doing well. I feed it flake food, and sometimes small live fish. I have noticed when these fish are frightened or mad they slowly form faded vertical stripes under the dorsal fin. They also form a diagonal stripe starting at the eye and ending on the top of the head. They are active, and aggressive, but rarely bite any other fish. They usually just flare their fins and dart at them. I wouldn't put these fish in anything less than a 75 liter tank. I don't think they are as aggressive as some people say. I would recommend this fish to anyone.
I have been keeping these small hardy fish for just a few months, but have already had 4 different batches of fry, 2 weeks apart each. I had thirty 6 week old fry which ate the new eggs and fry before I could remove them. The parents then turned on the oldest ones when the third batch was born, and killed quite a few before I realized what was going on. The parents don't seem to care that they are their children, when the new eggs are laid. But the fry are growing rapidly and are turning out to be as beautiful as their parents.
I've had jewels for a little over a year, they've only bred once so far and most of the brood survived. The way that I tell the sexes apart is that the females seem to have a slight indent almost between the eyes. The males don't seem to have this and it's much easier for me to tell like this because I'm color blind and don't pick-up the slight differences in color very easy.
Jewel fish fry can be difficult to raise. Use very fine gravel so the fry dont get trapped. Buy "fry" food to feed them as they have very small mouths and have trouble picking at larger adult food. They will starve to death if you don't. Dont plan on keeping any other fish in the tank with them while they are breeding or you will have fish with no tails!
I have two pairs of jewels right now. I have one pair of neons and one pair of reds. the neons are, in my opinion, the nicest looking fish ever. When breeding, they turn blood red on their bellies and mouths and bright neon blue scales all over there bodies. My red turn blood red all over and just a little blue scale on their bodies. They are super easy to breed. When I first got my two neons, they were about 8 cm in length, and in about a month of just having them, they laid eggs, about 150 of them. Sadly, all the eggs were lost because some of my other fish ganged up on them and ate all the eggs. If you want a nice, easy fish to start with, then this is the one for you.
I have a pair of jewel cichlids that I bought about 8 months ago. I originally bought 3. At first the male paired with one of the females, and was aggressive towards the other one. So I took her out and put her into a 150 L tank with some other fishes. The mating pair never did spawn...the female died. Since then I put the male and the other female into a bath tub outside with a small ceramic flower pot and some hornwort plant. After a couple months, I decided to clean the tub because there were lots of sediment on the bottom due to fallen leaves. I was surprised to find one young jewel, about 2 cm. I brought it inside and put it into a 75 L tank with a few swordtails and 3 young yellow Labeotropheus cichlids. They all live peaceably. I cleaned the tub again about 3 weeks ago, and now I'm surprised to have a wonderful school of fry. The parents are tending the brood carefully. The jewel cichlid, although of notorious temperament, are a relatively calm fish. They do not aggressively swim away from the net when I try to catch them, and they behave calmly in the whole netting experience. I'd recommend them to anyone interested in collecting cichlids. They are also good for controlling the snail population if the snails become a nuisance.