i have a 620 litre aqua one aquience bow front, i also have 2 tiger oscars sized about 4 inches at the moment, once i move them to their new big tank, i want to know what you guys think about this...
i want to buy 2 more oscars, maybe latino and 2 jack dempseys.
i know i need to buy them around the same size as my oscars i have now, but i need to know is my tank ok for the 6 of them once they all grow?
here is the new tank they will be in.

Your tank isn't big enough for four Oscars. I would also think twice about Jack Dempsey's as well. Putting these type of fish in with Oscars could cause problems as they can be very aggressive. If I was you I would go for Two Oscars and a few smaller tank mates. For example, a few silver dollars would be perfect.

so what sort of size would i need for 4 oscars?
im sure this tank is big enough, it seems more than big enough for 4.
and if you think jack dempseys are a NO NO, what about putting 2 texas cichlids in with my 2 oscars?
would that work?

silver dollars are greattank mates for oscars ive got 2 in with my tiger and the y get on swimmingly! they know there place and keep out of the way at feeding time they are good eaters and will eat a variety of live food inc small guppys!

I don't think your tank is even 150 UK gallons. That is no way big enough for four Oscars. You would need at least 200 UK gallons for that many Oscar. Jack Dempsey can reach 10 inches. Putting two of those in would be too much for your tank, plus you run the risk of aggression problems. I would definitely avoid Texas cichlid's, they can grow to 12 inches easily. Even though an Oscar is more than capable of sticking up for itself against one of these fish, your tank still isn't big enough.

If you put too many fish in your tank, you will just run into water quality problems once the fish get bigger. If you do attempt to put these fish in, you're going to need a lot of filtration as well, at least 2 large canister filters, or something like an Fx five.

Please take my advice, I've got a 125 gallon tank (6 x 2 x 2) with two Oscars and four clown Loach. The Oscars are between eight and 9 inches, two of the Loach's are around 7 inches, and the other ones are around 4 inches. I have got two 2028 eheim filters running on the tank. I have to change a third of the water once a week. Now imagine having four large Oscars? There is no way it would work. Also, 6 x 2 x 2 may seem big, it's not big when you've got a large cichlid swimming around in it. If large cichlids keep bumping into each other you run the risk of serious aggression problems.

its 136 uk gallons.
i dont mind having just my 2 oscars but i thought getting maybe 2 more fish would be nice, i wanted something with some nice colours which will be ok with oscars.
any idea?
I dont like the silver dollars.

If you want to keep fish with really nice colours, you need to keep marine fish.

If you want to keep two Oscars, you are very limited on what other fish you can keep. You could go for a blue acara, they're not exactly colourful, but they are quite nice looking. The problem you've got is any fish you are going to keep with Oscars need to be able to defend themselves and compete for food. Obviously to be able to do this they need to be able to grow to a suitable size. You may think your tank is big, unfortunately it's not that big when it comes to keeping large cichlids.

One fish that is very colourful and you might like is a red spotted gold severum. I've got one that is around 7 inches and it fits in with the Oscars just fine. However, I wouldn't have any more than just one of these fish with two Oscars because they can reach 12 inches.

Whatever you do, you're going to have two go for really good filtration. If you don't, you will be for ever cleaning the filtration.

i got 2 tetratec 1200's and 1 fluval 4, im sure thats enough for this tank, i was chatting to biggamehunter today and he told me that i have plenty of filteration for this tank, i got uv as well which should give me crystal clear water.
im stupid enough to overcrowd my tank and i only want the best for my fish, thats why i asked if i had enough room.
I do like the look of the red spotted gold severum, i might see if i can get 1,
so you think my 2 oscars with 1 red spotted gold severum will be ok for this tank and this filteration?

keep an eye on those tetratecs there not that reliable exelent for about 3 months then lose flow rate happened to me twice both 1200 s

Speaking from experience, I would go with the two Oscars than just one other fish such as the red spotted gold severum. Your filtration sounds good, but remember it's the nitrate that will build up quickly if you have too many fish. You can also get ammonia and nitrite spikes if you overload the tank.

you have good filtration for the tank AS LONG AS YOU DONT OVERLOAD IT the bioload will be far too great with more than 2 0,s and two smaler tank mates or 2 O,s and a sev .......if you want nice looking fish that can defend themselves and dont get too big have a look at my thread GREEN TERROR in the rescue section ....they are probably the best coloured freshwater fish available ...one of them and a blue acara would be ok with two oscars AND YOUR FILTRATION

I had never seen or heard of green terror but i have just fell in love, i cant believe how nice they are.
pity you live so far from me, i would of had him off ya.
i think i'll go with what you said and keep my 2 oscars and get a green terror and maybe 1 other fish, thanks for all the help OFL