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
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