Hi Asuka.
Sorry to read you are having such trouble with your new axie.
I read all of the thread and I notice that you have left food in the tank and also that you found debris in your ornaments. You have not tested your ammonia.
I too am paranoid! But I have kept fish for many years so I know that food and debris in the tank will create ammonia.
I have learned that ammonia is very bad for axolotls.
This is what I do.
I give them food on the end of a pipette. I take away all uneaten food after half an hour. I also take out all the poop at this time. I keep them in bare bottomed tanks with some Java moss to hide under or sit on top of and do 50% water change every 2 days. I have 9 tanks with 1 or 2 axies in each. It only takes half an hour to do the water changes. The tanks are at 15 to 18 degrees C. ( nearer the ground is lower temperature)
I will make a home for 2 of them in a big tank that I just bought (eBay £10

) but I will put in a sponge filter and take 6 weeks to grow some bacteria to eat the ammonia before my axies go in.
I have had my axies for 8 weeks and they have grown from 3cm to 11cm and are very healthy with fluffy gills and good appetite.
I post this to share my experience so that you can see if any of it is any use for you.
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