Please help. Discus turning dark

[kevind2007]

1. Please explain the problems with your fish. When did you notice the problems and did anything unusual happen that you think started them?

I bought 3 discus all 2.5 inches about 5 days ago. 3 days ago I noticed a dark or black build up on two of them. One has gotten better and the other is getting darker.

2. Symptoms (i.e. turning dark, excess slime, not eating, clamped fins, flashing, darting, clamped gills, white/yellow/green poop, hiding, headstanding or tailstanding, white on tips of fins, rotting or fungus, blisters/white zits on fish, bloated, cloudy eyes, wounds).

All three discus are still eating well and I have not noticed any other symptoms besides turning dark. The darkness looks like it is building up on the outside of the fish and not actually the fish changing colors.

3. What medications/ treatments have you already tried and what were the results. Include dosage and duration of treatment.

I have not used any medications yet. There is also a stingray in the tank so I have been trying frequent water changes and maintaining water quality before using medications.

Tank/Water

4. Tank size and ages, numbers and sizes of fish.

150 gallon tank. There are 3 discus each new to the tank and 2.5 inches. 1 Arowana 9 inches been in the tank about 6 months. 1 motaro stingray about 5 inch diameter in tank about 2 months. I haven't seen any aggression between fish.

5. Water change regime (What percentage and how often).

I do 30% water changes twice a week

6. How long has tank been running? Is it bare bottom? If you have substrate, what type and how deep is it?

The tank has been up and running for 9 months. I have a black rounded gravel substrate a couple inches deep.

7. Do you age your water? If you do for how long and what is the ph swing.

I use Prime by Seachem for treating water before water changes.

8. Parameters and water source;

Note: Water Parameters are important in diagnosing problems within a tank. If you don't own test kits for the following information, you can purchase them, test your parameters and post this info as soon as possible.


- temp 83 degrees Fahrenheit

- ph 6.6

- ammonia reading 0

- nitrite reading 0

- nitrate reading 20

What type of water or combinations of water sources do you use? If it is an RO/tap/well water mix, please list percentages in the mix.

- well water ____

- municipal water- All I use is tap water.

- RO water ____


9. Any new fish, plants or inverts added recently.

Just the 3 discus

10. Please tell us what you feed your fish and how often. This can be critical information for solving the problem so be as specific as you can.

I feed the discus blood worms mostly because thats what they were eating at the LFS. Stingray eats earth worms. Arowana eats talapia.

11. Include any pictures or videos you have which shows the symptoms. If you can't add them to this post, please provide a link to them.

I attached a picture. Please help. I'm new with discus but experienced with keeping aquariums. I just want to make the fish better.

[brewmaster15]

Hi Kevin,
Welcome to SimplyDiscus!

Looks like a few things here... first off the darkening is most likely because they are pigeon base, or at least the pic you posted looks to be. That means it has black pigment that can show under various conditions. Stress will do it and also dark background. Sounds like you have both there. The substrate is blackish in color and whether you don't see it or not I can guarantee the stingray and Arowana are not making these feel comfortable.. They are 3 lone 2.5" discus in a tank with an active predator Just 3 each 2.5" discus in 150 gal tank with no predators would be stressful.. You really want a group of 6-8 or more 2.5" in a tank that large.. Generally they do best in groups as when young. I would really suggest pulling them out and placing them in their own tank at least until much older...Go with a light back ground and no substrate and I bet you see less stress related pepper provided they are otherwise healthy.

hth,
al

[Altum Nut]

Had my reply ready but Al beat me to it...

First of all Kevin welcome to Simple Discus and sorry your first post ended up in the emergency room.

There are several factors you should have considered before jumping in with Discus.
It appears you just threw Discus in your established tank without quarantine period. This step is very important...reason being that your LFS is most likely on a central system where water would be shared by various other species with tanks containing dead or other pathogens affecting your Discus. Your playing Russian Roulette with possible pathogens or other possible illness which could affect your Ray and Arowana.

It is often suggested that when purchasing Discus...consider a group of 5 or 6 Discus. This helps with stress levels and minimizes chances to weaken their defence system. They are best happy in groups as they are schooling fish.

Another factor could be that your substrate is dark and your Discus having derived from Pigeon Blood Gene are susceptible to peppering with dark surroundings.
Lastly...throwing 3 juvie Discus in a large tank with a monster Arowana roaming above and a Ray roaming the floor could very well be stressing them.

My recommendation would be to get another 2 or 3 from the same source in a separate tank and grow them out as I don't see any positive results coming out of your present set-up.

...Ralph