HomeBroodExotics

I think you want something like this remineralization filter. https://a.co/d/88fBien

Are you testing for ammonia after adding dechlorinator and doing water changes? When you add dechlorinator to tap water chloramine breaks up into ammonia. If you do a bunch of water changes while your aqurium is cycling uou will just continue to add more ammonia. Stop changing the water and let the ammonia oxidizing bacteria do their job to eat the ammonia. You have nitrates without nitrites so the tank is likely cycled. You just keep putting more ammonia in it unknowingly. Have you tested the ammonia levels in your axolotls bowl?