One dead axie, worried about the other

2 months ago somebody gave us 2 mature axies, a black one and a white one. The black one ate lots and was very active. The white one was missing a leg, and he didn't eat much (sometimes he would chew on his food and then spit it out), but the leg was regrowing ok so we weren't worried. We didn't see any poop from either of them, which was weird.

Yesterday the white one died He was floating at the top of the aquarium, and his groin seemed very swollen and his cloaca (?) was open.


The black one has started eating a lot less now, and we're worried that the same thing will happen to him!


Conditions:
- weekly partial water changes, the test kit shows no (or almost no) nitrogen.
- it has been hot the last few days. the tank's at 26-27 C (~79 F).
- sand substrate now (and before we got them AFAIK)
- a few aquarium snails appear from time to time, we removed several but there are more


What happened? What should we do to save the black one?

Your temp is way to high, you need to chill it down to 20c, my tanks hover between 20c and 22c sometimes but 26c is way to high, you need to cool the tank down asap, there are a number of methods, chillers, ice bottles, cooling fans, turning up your ac, moving tank to a cooler room, removing tank lid to aid evaporation or even putting the axy in the fridge till the weather cools down. There may be other problems but this is probally the most immediate one.

Im sorry for your loss.
Your tank being that hot could have caused the problem. Please try and cool it down with some of the ideas that Ian gave you. If you cant get the tank temp down please put the black one in the fridge. What is their diet??? Is there in any cottonwool looking stuff on him/her?? Have you checked the ammonia reading??? Im guessing there is a problem with your water and combined with the heat the problem gotten a whole lot worse.............

Ok, I'll get an ice bottle and some fans on the lid ASAP, see what that does to the temperature.

I think the test kit we're using tests for ammonia, and as far as my colour comparison skills can tell there's none in there.


We haven't seen anything that looks like cotton wool on either of them.


We were feeding them these: Tropical Aquarium Fish Foods: Nutrafin Sinking Complete Food Tablets

It could just be the heat then. Work on that and things should get better. Keep an eye out for fungus and treat if you have too. In regards to the non eating, he/she might be a little bored with just pellets. Axies looove a nice juicy wiggly worm. I feed mine a mixture of earthworms, pellets and bloodworms. I also have some cherry shrimp in the tank for them to snack on if they can catch them. The shrimp make a really good cleaning crew as well.

I think it might be just the heat. In that extreme I think I'd personally go as far as putting the axie in the fridge so it stas cool. You will need to be religious about changing the frozen water bottles since constant changes can be more stressful than heat.

It sounds like you really need a chiller. I know I will need one when summer hits here! They are expensive but I think the are worth it for the peace of mind of having the temp stable.

Otherwise work out the coolest room in the house and keep the axie there. As low to the ground as possible

Sad to hear you lost your axie it can be quite upsetting. I have lost an axolotl the same way, it was unable to digest the gravel it had eaten at the petshop. but in your case it sounds like its unable to digest the snails it thought were delicious. cooling it down is the right thing to do, it will slow your axies metabolism so that hopefully it can break down the rest of the snails, before they try to poop it out lol.(I've also heard that people put them in a tub in the fridge) If the snails you found in the tank were quite large compared to the size of an axolotl egg then you might need to find a vetenarian who deals with amphibians and similar pets.
I hope the little guy makes it through