Rescued Axolotl is essentially doing a handstand in water, backside continues to float upwards.

[Brad Taylor]

Hi. I rescued an axolotl named Gary from another owner 2 days ago. Immiedietly after making the transfer and moving Gary to my house, I have noticed that he is having major trouble keeping his backside on the bottom of the tank. Part of his gills were out of the water for a little while during the transfer, maybe that could have something to do with it? I even found his entire body floating (upright, not upside down or anything) near the water's surface at one point, but for the most part his front legs remain on the sand but his back legs and tail float up, almost like he is doing a hand stand or something. I am new to axolotl care and am not sure what to do. I assume it is like fish (which I am well-versed in) and is some sort of swim bladder issue, but I am not sure, and if it is I dont know how to care for it. I moved him to a smaller container at one point and attempted to gently rub his sides to expel trapped air, and while it seemed to help it didnt ultimately change anything. Ammonia was slightly higher than normal so I added extra Prime water conditioner, but besides that I dont know what else to do. Any help would be greatly appreciated. I am not able to upload any photos because it says the files are "too large"

 

[wolfen]

axolotls don't have a swim bladder so when air gets trapped they end up floating, this can be quite stressful for the axolotl (and owner).
tub the axolotl in water that is shallow enough to allow for his feet to touch the ground, change water daily using cold dechlorinated water.
is the tank cycled for an axolotl?, this is to make sure that the filtration/tank is able to cope with up to 4ppm ammonia per day.