I am new here, Discus behaviour

[mykey01]

First of all, I am new here and I like reading the forum for sometime before I decide to join. They are very informative and give a lot of tips to improve my discus keeping. I have been keeping fish in aquarium for almost three years but only about three months ago I started keeping discus. I have three discus in a 29 gallon tank: two turquoise snake skin (according to the seller, mix of red diamond x blue spiderweb) and one blue diamond. The other occupants in the tank are 4 Siamese algae eater. I've got the fish for about 3 months. A concern I have is the two turquoise discus are ganging on the blue diamond. In the tank they somewhat establish the hierarchy being one turquoise in on top, then follow by either the other turquoise or the blue diamond (depending the mood of the two). The top discus chases the other two but more towards the blue diamond. Is it common two same coloration of discus will be somewhat friend but not to the other? I estimate they are about 5-6 month old so they are still very young so I do not think the turquoise are pairing. Or is it just because I only have three?

[Merrilyn]

Hello Mikey, and a very warm welcome to the forum.

We need to remember that discus are cichlids, and as such, they can be aggressive with their own kind. It's very normal for one fish to become the dominant fish in the tank, and for another to be at the bottom of the pecking order. With three fish there's not a lot you can do about it. Just keep an eye on them to make sure the little one gets his fair share of food at meal times.

Quite often the leadership changes, with the underdog suddenly becoming the dominant fish. If things are looking too bad, you may want to add another fish to the tank, although with a 29 gallon, you're right on the border of your limit now, with one fish per 10 gallons.

For the time being, I'd suggest just keeping an eye on them to see that the aggression doesn't get out of hand. Sometimes it's necessary to separate the bully and put him in another tank. These fish are young. I think I'd just wait and see how things progress.

[mykey01]

Hi Ladyred, thank you for the reply. I'll monitor them, actually, I am whenever I can. Up to now all get fair share of food. The blue diamond always start feeding first than the other two.

[FishLover]

Bigger tank and more Discus seems to less the aggression. I used to have 6 discus in my 125 g tank and one is getting chased all the time. Last time I added 5 more to the tank, they don't chase the poor guy/gal like crazy any more.

Somepne said odd number is better than even number. I'm not so sure if that is true or not.