I set up a 150 gallon planted tank this summer with the interest of making it a discus aquarium. Last week I bought a discus (2") and he has been doing fine. Today, I bought two more, one that's the same size and one that's 1.5". Unfortunately, the one that I had first has been nipping and attacking the other two. Since it's such a large tank, I would normally think that the discus would be able to hide, but it's been brutal. There are about 20 other fish in the tank, including roseline barbs, clown loach, and rams. I have a 10 gallon quarantine. Not sure what to do... I want to be able to keep all 3 together successfully and add to the group by getting more discus, but I dont want any more discus to be attacked by the current aggressor.
Wow, I don't want to offend you but I have to tell you that you've made a number of common mistakes made by new discus-keepers. caused by doing insufficient research on discus before getting started with them.
Among them are:
- Buying small very young discus whose immune systems are largely undeveloped, causing them to be overly susceptible to a wide variety of health issues without proper treatment to grow them out successfully.
- Getting less than a minimum number of 5 or 6 fish to more or less assure the least aggressive pecking order behavior, and avoid serious bullying.
- Adding more/other discus at different times, perhaps from different sources, and different tank environments without proper acclimation and suitable quarantine procedures.
- Placing very young fish in too large of a tank initially, in a community set-up with a good number of other species of fish with differing temperaments & water conditions, this again without quarantine, probably in an undesirable planted set-up. The roseline barbs & clown loach in particular are fast-moving, active fish which can intimidate small discus very easily.
You have created a seriously problematic situation that you can't now undo, but here's a way of making the best of it & hoping for a satisfactory result:
- Remove your 3 young discus to the 10 gal bare-bottom tank that has either been cycled, or that you can & will do large daily water changes to until the tank does become properly seeded. Ensure the tank receives necessary filtration, heat temp suitable for discus, and lighting if need be. Feed the fish several times daily with good quality foods.
Get at least 2 or 3 more of the same discus from the same source as before and add them to the 10 gal tank with the other 3. You have no other facilities for proper QT, so take your chances with that & hope for the best ( i.e. that no undesirable cross-contamination of any kind takes place). Place a light colored lining under the bottom of that tank, and the back & sides as well so that the fish will not feel threatened or intimidated.
Maintain daily wcs & multiple feedings in the clean bare-bottom environment until they reach something over 3"- to 3.5" in size, at which time you can consider putting the group into the 150 gal tank with your other fish.
That's my best advice to you at this stage.
Best of luck to you.