I am weak...

[brewmaster15]

Could the nitrite test just be faulty? Changing water every day and still reading nitrite would have me wondering. How big is the tank.
Great looking discus!!
Yes add some filter media from your main tank. That’s the way I always qt new fish. 2 discus even that big should not be giving you a daily nitrite reading. If your discus look fine it’s the test kit. I’ve found nitrite worse than ammonia. Any nitrite in a tank and the fish show there’s a problem.

Brian that heavy shaking is for the nitrate test not nitrite. Nitrite is the 5 drips. Clear good purple bad .

Tom good points .. the only thing to note on the nitrites is the salt added protects the fish from nitrite poisoning.. blocks its uptake and the subsequent brown blood disease... so the fish could be "ok" even though theres notrites there.

[Second Hand Pat]

Whenever I get new fish I always expect a mini-cycle as the bacteria adjusts to the bio-load of the fish. I also try to add one or more cycled sponges to the QT as a starting point. I do at least 50% daily water changes the first week. I always add/replace salt for the reason Al started.
Pat

[Johanna]

Ok, I'm going to get new test kits today and let's see what they say. I think the nitrite kit is also quite old, there aren't a lot of the reagents left anyway. PH is still 7,1 measured just now, which is a couple of hours after a water change. I'm starting to believe the filter wasn't cycled to begin with, even though there were some nitrates. I'm used to seeing low levels in the planted tank and there probably should have been way more in the bare qt to indicate a full cycle. I think the NO2 test is working as didn't show any nitrite when I tested the water a day after feeding the empty tank, before getting the fish.

Tom; the tank is 125 l. An honest question: aren't you worried about bacterial cross contamination from your old fish to the new? Using established filter media would easily solve this problem but how big is the risk, I wonder.

What would be the first signs of nitrite poisoning, so I know what to look for?

[brewmaster15]

Tom; the tank is 125 l. An honest question: aren't you worried about bacterial cross contamination from your old fish to the new? Using established filter media would easily solve this problem but how big is the risk, I wonder.

this is a valid concern. One of the reasons for a long Qt is to allow the new fish to get used to the bacterias and viruses that the existing fish have. This happens over time usually by small drops of moisture in the air and human mistakes. Thats why I use 6 weeks and a hero fish. Cross contamination can happen to the new fish if you use media from your existing tanks. I prefer to not do this.. others do it as Tom suggested. If the new fish will go with the old I wait until they are fully healed and settled in. I think people don't always understand that transport damage to the slime coat can take a week or more alone to heal and thats the fishes primary defense against pathogens.

What would be the first signs of nitrite poisoning, so I know what to look for?

darked appearance, labored breathing and skittish.

basically their blood can not carry enough oxygen.

[Johanna]

...The local fish store didn't have ammonia test kits so I was only able to buy a new NO2. It still shows orange but looks like it's lessened from the morning. Nitrate level seems to have increased too around 12,5 mg/l mark, so maybe I'm over the worst of the spike. The fish are still looking good. Except I noticed the slightly bigger, more aggressive one has a few enlarged sensory pits around it's head, Not sure if my water quality problem might have already caused them or if they were already there when I bought them. To be honest their tank in the store was overcrowded and looked a bit dirty for a discus tank. I suppose a few weeks in quarantine in very clean water will take care of that once the nitrite clears.

I think it is best anyway to delay the deworming until the water issues are completely settled and they've had time to recover in clean water.

Here's a video of them from tonight. (The plants floating in there came with the fish, not from my main tank! Their tank in the store was full of it and some got into the bags, so I thought why not throw them in as well for some familiar organic matter.) What do you make of the behaviour, hovering over the filter and nipping at it? Sometimes it's more aggressive. They aren't doing the breeding shakes, just nipping at the filter and the wood and even corners of the tank.

Cloudiness of the water is due to Nitrivec.

[brewmaster15]

The pits are probably from the nitrites. One theory on water quality issues and discus facial pits is that nitrites/nitrates can act as dialators.. I havent seen any proof of it in articles but its plausable,imo.

I think I will double down on my earlier guess that you have a pair.. And will probably have spawning soon.
Al

[jeep]

They sure are big! And they look good. Keep up what you're doing and they'll be fine!!

[Johanna]

Well. They did spawn today. One lays eggs on the filter, the other one follows and eats them. It's still going on there, I was about to do a water change but let them be when I noticed. He (?) does not even try to fertilize them. But he didn't really seem to be interested in breeding, except for lazily nipping at the filter sometimes. The female did all the work.

The nitrite is almost gone so I don't think a water change is necessary tonight, but should I still do it, or let them do their thing in peace?

[brewmaster15]

Well. They did spawn today. One lays eggs on the filter, the other one follows and eats them. It's still going on there, I was about to do a water change but let them be when I noticed. He (?) does not even try to fertilize them. But he didn't really seem to be interested in breeding, except for lazily nipping at the filter sometimes. The female did all the work.

The nitrite is almost gone so I don't think a water change is necessary tonight, but should I still do it, or let them do their thing in peace?

The male is probably inexperienced young. Assuming they are siblings males mature slower than females in most cases. I would leave them alone for now and let them finish their test run.

[Johanna]

LOL. Now the other one is laying eggs, so yes they are definitely both female. Do I need to get one more

[Second Hand Pat]

LOL. Now the other one is laying eggs, so yes they are definitely both female. Do I need to get one more

LOL Johanna, I think a fair question is what do you think?
Pat

[brewmaster15]

lmao.. well thats just too funny. lost that bet.

[danotaylor]

LOL. Now the other one is laying eggs, so yes they are definitely both female. Do I need to get one more

That would depend on your goals. If your goal is to breed and raise fry, then a male would help lolz