Originally Posted by Bacon Is Good
What a shame. You changed to much water too soon
Changing the water does nothing negative, there is no beneficial bacteria in the water (none worth counting anyways).
If it is an established tank (several months old at least) then half the bacteria will be everywhere else in the tank, mostly the substrate but also on every hard surface. It would have been best to keep the old media and just clean it in old tank water if it had a lot of debris in it. Pads can be reused forever until they disintegrate or loose their shape so water goes around instead of through them.
But loosing the filter media will set you into a mini cycle as mentioned, but thankfully not a full cycle (assuming established tank).
A gravel vacuum should get most of it. I think something is wrong with your nitrates reading though. I've never heard of a test that goes up to 560 ppm so I'm assuming your finger just hit an extra key and it is really 60 ppm which isn't at crisis levels.
If you have 5 ppm Nitrites, frankly I'd be surprised the fish are still alive. Do you mean 0.5 ppm? Or are you already using Prime?
Ammonia at 4 ppm is at death level too, the only counter would be if you have acidic water and it was ammonium instead of ammonia.
Keep doing 50% changes daily until it gets back under control, and use prime as described.