Tank mold

Hi there guys,
We have just upgraded our axolotl tank to a lovely spacious four foot model. Our two axies Moxie and Xenie have settled in nicely over the last couple of weeks but we seem to be experiencing problems with what I think is mold.
It only forms overnight when we have the tank lid on. In the morning I find a kind of scum floating at the sides of the tank. It seems to be a clear jelly with white specs floating in and when I take it out it's quite stringy. It's not a massive quantity or anything, I just scoop it out with my fingers and it doesn't reform during the day. Our water parameters are perfect and both axies are doing well, stuffing themselves as usual and going for leisurely strolls, popping up for the occasional air bubble. I couldn't find any reference to anything similar in the forums so I just wondered if anybody had encountered something similar or knew what it was?
As always, thanks for your time and wise advice! roud:

I had a somewhat similar problem and this is what a moderator suggested that it was to me.

"Proteins from organic matter in the water are processed by bacteria and the resulting proteic derivates accumulate in the surface as an oily film. You can use paper towels to absorb the surface film. In order to avoid the build up make sure to keep adequate maintenance of the tank, eliminating uneaten foods, feces or dead plants. In some cases other bacteria or perhaps fungae can grow on this proteic film which looks like white specks floating on the surface."

The white specs that you mentioned sound like the ones mentioned here. I'm not for sure if it is what you are experiencing exactly, but its a thought.

Thank you so much, that's most helpful. I don't think it's a serious issue as they are both clearly healthy happy and alert but I thought I better check it didn't signify some terrible impending problem! I'm working on a way to make sure they get air flow through the tank lid over night, it seems to produce a lot more condensation than our old one did.