Axolotl gulping?

[pwbonz]

So my axolotl has been gulping as if she can't breathe and her gills are very bright, leading me to believe she's not getting enough oxygen. I had put her in a separate bin with fresh dechlorinated water and an airstone to pump some air in there and she was fine for several days aside from taking longer to eat her worm (she spit it out a few times before eating it which isn't like her). So I put her back in the tank yesterday and she seemed fine but she was just doing the gulping thing again. I would think the tank is low on oxygen but I have another axolotl in the same tank and she's doing just fine! I'm so confused and don't know what it could be!!! Any suggestions or ideas are very welcome! pH = 7, ammonia and nitrites = 0 ppm, nitrate = around 20 ppm, tank temp at 60 F right now and never reached above 64 F.

 

[EasternRomioi3]

@pwbonz

Is your axolotl doing better? When my girl starts to do that, I change her water and it usually works.