Eating Air

My axolotl was fine when i introduced it a few days ago, now when I did a water change it is consistently gulping air from the top, and staying in the corner. I have a feeling the temperature may have risen. I have de-chlorinated the water and used half-rainwater (clean) for the water change.

What are your ammonia, nitrite and nitrate readings? And temp? Mel

Axolotls also possess rudimentary lungs. They will occasionally gulp air from the surface in addition to taking in oxygen through the gills. But if your axolotl is gulping air excessively, I agree there may be something wrong. In addition to the readings melfly asked for, what kind of filter are you running?

I'm using a Stingray filter. I don't know how to check for ammonia, nitrate, and nitrate, but I'm pretty sure it's not too bad as I have a lot of live plants and only one axolotl. This tank is also kept very well. The temperature is slightly high, as the radiator nearby the tank got switched on today!

Ok so you need to get a thermometer and a freshwater master test kit.
Thermometer will be about 2 quid test kit about 20 ish
You need to make sure you keep the temp under 20 degrees, otherwise your axie will become stressed, ill or die.
You need to moniter the ammonia, nitrites and nitrates as you cannot guess what they are from looking at the water. If the tank has not yet fully cycled your axolotl could end up in toxic levels of ammonia or nitrites, this will also cause stress, illness and eventually death.
These are important things you need to be able to provide your axolotl with a decent quality of life.
Mine do gulp water now and then as Kaysie mentioned they do have lungs and will do this from time to time. But if it is constantly something is not right.
If you think your water temp may be too high you could fridge him until you get hold of the thermometer etc. Or put him in a large tub with dechlorinated water in a cool place in the house.
Hope this helps
Mel