Hi All,

I have a large tank that is home to my much loved Oscar (Cavey 12") and his friends:-
2 x Firemouths
2 x Blue Acara
2 x Gold Sevrum
1 x Green Terror
1 x Common Plec

I am wondering what are the possibilities of being able to introduce another O ? I have 2 big eheims on the tank which seem to cope fine. .
Is this a complete no go ? The pet shop were trying to sell me an 8" O the other day telling me that it would be fine, but thought it best to do some research first..

Many thanks

Stav

Welcome to OFL. When you say you've got a big tank, exactly how big? Don't forget that severums themselves can reach 12 inches, common plecs can get to well over 18 inches fire mouths, acaras and green terrors can can reach 8 inches. So if you are thinking about adding another Oscar, you're going to be looking at a tank well over 200 gallons

The tank is 150 odd uk gallons. The other fish arent really that old so i think your right. . Should stick to what ive got, till I upgrade again.

Can it be done though ? Have read lots of things that say its a no go. . .

What are the exact dimensions of the tank? You've got various fish that can reach 12 inches or more. Also, you should be careful with fish like green terrors. These type of fish can be extremely aggressive. I'm not saying he will have problems, it is something that you should bear in mind.

I think you might be pushing it by adding another Oscar to be quite honest.

Adding an Oscar to which already houses a single Oscar can be fraught with difficulty. As you cant sex Oscars there is no way of knowing that our not going to end up with 2 males which will fight or an aggressive Oscar that doesn't want to share his surroundings with another Oscar. A word of warning as OFL says the fish you have can become extremely aggressive in adulthood so be prepared for fireworks in the tank one day.

If having listened to what OFL and dinger have to say you still want to add another oscar then first off just put one in and see what happens. If they fight and any get injured then put a divider in to separate them. Leave for a week then remove the divider. If they still dont get on put the divider back in. Leave for another week and then put the aggressive one into the others half. If they get on remove the divider. If they still fight such that one is getting injured then remove the new one and give up.

If you manage to get them getting on ok this might not last. As dinger said you could end up with 2 males that just wont get on. Also have you thought about what if you get a breeding pair. You will end up with your oscars at one end of the tank and all the other fish at the other end, with none of them being happy

Hi Everyone,

I thought it may be worth adding my question in this topic as it is pretty much the same thing.

Up until last week i beleived a i had a lovely pair of oscars.

Finally i watched some eggs being layed, while unfortunatly the other one followed behind vacuming them up. I just thought 'oh well' this happens. The next day got really interesting as they decided to swap roles. My "male" oscar layed eggs while the other vacumed them up.

So to my question. I obviously want to find a suitable mature male. Should i be looking at a similar size, smaller or larger one. As they are in a large tank would it be a wise choice to add a male with 2 females and see which one gets lucky or remove one?

It would be a shame to see them parted as they get on so well, wonder if i could get a sex change done on one of them?

Both females are around 9 - 10 inches long.
Any advice is appreciated.

Cheers