I currently have 2 jack dempseys and 1 tiger oscar. They are all young. I bought all 3 together. So far they all get along. My ? is are they compatiable as they grow? Im new here, and new to owning my sweet babies. Right now they are in a small 10 gallon tank. They are all 1-2 in right now. In about 2wks Im upgrading there tank to our 100 gallon. I guess my concern is will my oscar eat them later on? SorryI have been doing alot of reading and Im not sured weather or not I should not put the dempseys in the 100 gallon tank w/ the oscar? Thanks!!

staceymomx3 wrote:



In most cases these fish will live in peace and be happy but this is not always the case oscars can become aggressive as the mature, at feeding time, bredding time (if they end up paired) & also sometimes they bite things (other fish) just because they are curious. BUT PLEASE GET THAT 100gal TANK AS SOON AS POSSIBLE!!! A 10gal TANK IS JUST NOT FAIR ON THE FISH!! I would recomend at least a 120gal - 130gal tank min But a 100gal will be ok if you really can't afford a bigger tank.... So it's your call on the jack dempsey, But they should be just fine as long as your move them to a bigger tank ASAP.

assuming you get your tank upgrade i wouldnt worry to much about the oscar hurting your jacks. actually as they grow i would be more concerned about the jacks putting the beats on your oscar. every fish is different and there is no predicting how large cichlids will interact but when it come down to aggression oscars rate fairly low on the scale definetly lower than jacks do.
i have jacks and they are definetly more aggressive than any of the four oscars i now own. not to say they cant cohabitate together but its alway my oscar i worry about getting beat up not the jacks.

hope some of this helps



btw a 100 gallon tank would more than large enough for an oscar and a couple of tankmates the size of jacks.....

i would also be more worried about the two jacks beating up yr oscar!

please make sure u get yr upgrade!!!

just outta interest (dont mean to hijack thread) but i know that if u have two male oscars ur in for trouble when they grow up, and when buying two young oscars its purley a lotto and have to have yr fingers crossed that u hopfully have a male an female, is it the same with other fish? say if u could not tell male from female JD's would they fight when older if u had 2 males?

If they grow up together they shouldnt be overly agressive tword each other. How ever you need to get your tank NOW it will take weeks to cycle it properly. It wont be long at all before that 10gal will be septic and you wont be able to change the water fast enough.

Thankyou. Im going to get my tank set up next week. How long do u think it would be before I can put them in it.

I have an Electric Blue Jack in the tank with two Oscars and the get alone fine. Actually the two Oscars are the ones that fight.

j-mass, got any pics of yr electric blue u could post??

i have 2 oscar and 1 male jack they do fine. i wouldnt see a problem but ur jacks mightpick on the oscar.

I have 2 O's and a Female JD. they do great!

I have a male JD in my tank with two Os, so far so good, but the true test is when they reach sexual maturity. It has been done, but be prepared to rehome if it gets ugly, as each personality is different.

Most would say a tiger is more aggressive than my lutino, but that is far from the case, my lutino runs the whole tank and although others may fight like cats and dogs, NO ONE ever messes with him!

JDs can be more aggressive, but only time will tell! Good luck!

ive got 3 o's and 3 jacks, and... if anything... the jacks are the guys to watch for sure lol. those jacks dont even like other jacks! i had 3, 2 paired off, they beat up the 3rd, then the pair turned against each other, and i had to split them up too!!! im glad i have some big aquariums or im sure i would have had to rehome one atleast lol.