Hello, This is my first time here and I would just like to thank all who respond. I have two tanks set up and both are cycled. One tank is 38(36x12x17h) gallons and the other is a 135(72x18x24h) gallons. The 38 gallon will be empty in a few weeks as it has some fantail goldfish that a co worker is taking. Someone from my building was moving and they had some young fish that I took as they were going to "get rid of them". Now for the problem, I have 2 oscars 3-4",a dempsey 2",2 bala sharks 3",pleco 10". From my neighbor I received 2 rosy barbs 2",2 pink convicts 2", red devil 2" blue gourami 4"...
Now the problem I see is the devil and what to do with it. I am thinking of putting the convivts the barbs and the gourami in the 40 and keep the oscars,balas,dempsey,pleco and devil in the large tank. right now after 2 weeks all is fine but I know a few months from now this will be a real rowdy tank. filtration is no issue as I have 3 large filters(cannister and hob).
The oscars and balas I have had before and would really like to keep them. Any suggestion would be appreciated and sorry for the long post.

Umm..... never kept red Devils myself but I've read several times how aggressive these fish can be. Personally, I wouldn't mix the Oscar and a red Devil. However, who knows if there would be trouble? You might get away with it, it would be hit and miss really. Maybe you should put them together, monitored the situation and then decide what to do. Like I said before on another thread, I've had no experience with red Devils, maybe someone else can give you the benefit of their experience, they might tell you to forget the idea altogether as it would be a recipe for disaster. Remember that red Devils can get very big, just like Oscars.

Welcome to the site, first of all!

Considering your possibilities regarding available tanks, I would think there are no better solutions really than what you said yourself, except finding a new home for the Red Devil. The 38 gal will be too small for it once it reaches adult size, so not much else you can do.
Neither have kept any yet but from what people say, they tend to live up to their name. I'd probably rather try to keep it with convicts than with Oscars otherwise (in a big tank).
As Penn said, maybe you'll be lucky keeping it with the others in the big tank, especially if it's quite a long tank, who knows. Sometimes things like that do work, but I'd be prepared for trouble in a while. If you decide for that, it's probably best they grow up together.
Hope someone else has experiences to share, and good luck anyway!

I will do that and keep an eye out for aggression. I really dont want to partition the tank as that defeats the purpose of a large tank. My only hope is the oscars will grow faster and hopefully bond so the devil wont even try to pick a fight, but whatever plays out I wont let the oscars be unhappy. Thanks for the help.

the bala shark isnt gonna live much longer, i can tell ya that. even the oscars will tear him apart. you could put the convicts with the oscars they can hold their own. as for the red devil, as he gets bigger, even in a very large tank, he'll want the tank to himself. so hes a threat to all fish. for now, keep alot of hiding spots, hopefully the devil will find a comfortable spot and stay there. the oscars will not hide, but they'll learn to stay away. i've had oscars and devils about the same size together so u might be ok. just keep an eye out for that devil.

MetalHead is right i've owned Red Devils n the past. The ones i've had were very aggressive. One of the ones I had killed off all its tank mates except for the pleco in one day. They are greedy fish and I will never get one again unless it will be in a tank all by itself.

I have oscars, 2 red devils and dempseys together for quite awhile and have had absolutely no problem "YET"!!!
My devils are very tame and friendly with my other fish.
He swims around like there is no one else in the tank.
This is just my experience and probably just my luck so far. It also may be that I basically brought everyone into the tank when they were just squirts.

u seem to have gotten lucky. devils are usually extremely territorial and and from what ive seen rarely swim in around. (unless you have no rocks, plants or caves which i would never recommend.) it could have been because u introduced them to each other early on. but i did that and didnt have quite the luck youve had. how big are the fish?

yep think its luck but then again everyones afraid of me, lol so they better behave. I have quite a bit of wood, rocks and some artificial plants incorporated with hiding places. Sssh! but I just got me a green terror too and so far so good.

Oh! the red devil is about 4". My biggest oscar is about 7", depsey about 6" and my terror about 3".

Thanks to all who responded, just to update as it has been a few months. The 2 oscars 6",2 balas 5",devil 4",dempsey 4",convict 3" and pleco 8" are in the large tank and while the devil does seem to chase the convict and the dempsey, the dempsey quite aggressivly there are no nipped fins and when the dempsey is in his cave he will defend and move out the devil. The devil shows no aggression towards the oscars but the oscars do chase the devil every so often. The bala sharks I have always had with oscars and they are just to quick to be caught by any fish in the tank and they seem to be completely ignored by all.
Balas make a great cleanup crew and they are to large for the oscars to see as food so they are a non issue in this tank. Again, thanks for the help.

i'd love a dempsey but i haven't got the room

Hopefully everything stays a-ok in your tank welby. Sounds like a great mix.