Please advise w/ new 125 gallon

For a tank that size, in addition to the cichlids, you could easily have a school of silver dollars or some of the larger rainbowfish, which will help to keep the cichlids distracted from each other. You could certainly try a JD, as my own experience with that species is that it is not as aggressive as its name would indicate.

For catfish, synodontis ocellifer or decorus would be a good choice. And a standard pleco, if you promise to feed it lots of zucchini and red leaf lettuce (because algae alone is never enough).

I have my two O's with a green terror and a common placo. No trouble with them, the GT is much quicker than the O's. No fights even at feeding time.

I have two Oscar's with a Green Severum and a Cuban (Nandopsis Tetrachantus) in a 125g. My Oscars get along like house on fire but i have no idea what sex they are. The Severum tends to mind his own business and stay out of the way most of the time and the Cuban (whilst he does chase the Severum every now and then) is not aggressive at all and is the most beautiful fish i've ever owned. Maybe i've been lucky with my individual personalities.

My advice to you is to not put anything too aggressive with your Oscar(s). IME they are not aggressive, just greedy and don't pick fights with other fish for no reason. they cannot stand up to the more aggressive SA or CA Cichlids.

JD's and Green Terrors make good tankmates as long as they are smaller than the O's (but not too much smaller) but there's no better tankmate for an Oscar than another Oscar (providing you have the tank space). Silver dollars are good target fish but you need at least 4 of them as they are a shoaling species and are very uncomfortable on their own. They are way too fast for the clumsy big Oscars and will eat all the little bits of food that your Oscar's chew up and spit out into your lovely clean tank.

Just some of my experiences, hope it helps and good luck!!

I don't have photos as i haven't got a camera good enough to do them justice. I have some decent pics of my Oscars that a friend took so i'll see if i can find them.

I think my Oscars are a male and a female as they have started cleaning a piece of slate and digging pits in the sand. They have also started lip-locking and tail-slapping. There is still the possibility that they are both female but i hope not. I suppose i'd better be prepared incase i need to re-house the Severum and the Cuban in one of my other tanks.

As i said, i have been very lucky with the personality of my fish. My Cuban is very mild natured compared to what i have read in species profiles and considering they are related to the Jaguar cichlid.

The best advice i can give is to do your research thoroughly before you go and buy your fish. There is still no guarentee you will get it right though. I bought my Cuban to go in with my Texas cichlids but he was severly picked on and i thought i'd try him with the Oscars and he's been with them 6 months now with no problems.