One of my discus has a black tail for a week now, has been doing water changes everyday. I think its the discus plague, what is the most efficient way to cure it?

I also have a discus that is always being bullied by our first discus whenever it goes near a smaller one, what can i do to lessen the aggressiveness?

I have a planted 151L tank

There are 4 yoyo loaches, 4 clown loaches, 5 neons and 1 silvertip tetra, 2 chocolate pleco and 1 black whiptail.

Ph 6.5

Nitrite 0

Ammonia 0.50ppm

Nitrate 20ppm

I have high ammonia and nitrate levels and no nitrite-so how can i solve these two problems?

How many discus?

Your nitrate is within acceptable levels. Add more plants to your tank.

As for ammonia, do WCs and use a good water conditioner like prime.

Have you treated your discus for worms/flukes/hex?

Did you get them from a shop or a good breeding?

Are you matching the water parameters when doing your water changes?

Are the ones going black the smallest?

And I agree with Josh - how many discus do you have?

Hey.

I have 3 Disucs. Blue Troq, Red zebra, Red dragon.

Have you treated your discus for worms/flukes/hex?

My Red Dragon Discus had Fin Rot Before. About 2 weeks ago. Yes, the smallest one is the red dragon discus. I bought him from a breeder on trademe and after purchase, we found out that his fin are rotting. We treated him in another tank. After he got better. We placed him with the main tank again. Yes. Whenever we change the water. We try our best to match them.

If it's discus plague your discus will all be at a corner in the bottom of the tank. They will be all black and slimey and would be dead by now.

this is the image of the red dragon and its blackened tail

It needs to be dewormed.

But that is not plague or anything like it.

The fish looks slightly stunted but if you do lots of waterchanges regularly you might be able to make a noticeable difference!

The spots you might be noticing are more likely to be what is called peppering; a trait common of checkerboards and other pigeon bloods.

HTH

I would say give them a good worming, also only have 3 is probably not a good idea if 2 have paired off the 3rd will get a hard time..

so how would i de-worm them?

they didn't have white faeces or anything...although their faeces are like quite crumbly-like

would 4 be a good idea as that's the only number I can fit into the tank?

Looking at the pic, there is nothing wrong with the discus. The colour is just how a discus with pigeon strain looks. Some of them have very nice black tail and some are just clear. Pigeon will always have the black dots or peppering especially when they are excited, in breeding mood, breeding, stressed and dark environment. To lessen the peppering you can paint all sides of the tank white and make sure the fish is not stressed.

but when we first bought him the tail was white...well it was clear like normal discus tails

now My red zebra is hiding probably because my red turq has been bullying it heaps whenever it goes near the red dragon...how can i lessen that

now My red zebra is hiding probably because my red turq has been bullying it heaps whenever it goes near the red dragon...how can i lessen that

You cant.(as far as I know with a tank that size) The red turq and red dragon might be becoming a pair. Somebody in the post further up mentioned that the odd one out will be picked on. Its normal with cichlids

so should i just get another discus and some more schooling fish?

The changing of the tail colour from clear to black is perfectly normal,

and quite common with the pigeon strain as the fish matures

Red Zebra?

Your best bet would be to get rid of the one being picked on provided the other 2 get along just fine.