Illness/Sickness: Bubble on his head

Hello-- my baby Axolotl has a bubble on his forehead. I bought him last night, and noticed it after I got him home. He seems to be acting okay, he's been eating well since I brought him home. This is my first one and I'm learning everything for the first time. His own tank is being set up as we speak with only sand (didn't realize he was supposed to be by himself with no rocks until I read about him last night). Any help would be greatly appreciated.

Welcome to the forum

I am happy to read that you are setting up another tank for young Axel. What sort of fish do you have in the tank with him? Is it possible one has sucked on his head? I would suggest putting him in his new tank by himself.

Have you cycled your tank?

Take a look at these articles:

Caudata Culture Axolotl Articles

Axolotls: The Fascinating Mexican Axolotl and the Tiger Salamander

Not sure on the lump my self.

Thanks!
There were Cory catfish (different breeds), two bristlenose plecos, a few zebra danios, and two long-finned tetras. And some assassin snails. The interaction that I saw between him and the bottom feeders was honestly kind of cute. He'd walk towards them and they'd swim at him, they'd get close to each other, and then they'd swim away. Or he would walk over them and keep going. He would lay on the pleco'a tail. I noticed the bump very shortly after I got him in the big tank, and there wasn't any fish sucking on his head (I was watching him closely for a good hour after I put him in there and noticed the bubble in the first 10-15 minutes). It hasn't gotten any bigger so far. I'm starting to wonder if it's possible that it's a birth defect? I noticed last night that he has an extra hand growing out of his right leg. Didn't notice that ? I'll see if I can post a picture of it here pretty soon.

Do not keep Axolotls with fish. Axolotls are not fish. Plecos can cause particularly nasty damage to an Axolotl. Your Axolotl will likely eat any of your other fish that are small enough to fit in it's mouth.

It is likely the lump has been caused by the other inhabitants of the tank.

Also, again, have you cycled your tank?

I took him out of the other tank and put him in one by himself. There are no fish in with him now. The bubble may have been caused at the store I bought him from, because there was no interaction between him and my other fish before I noticed the bubble on his head. The following interaction was harmless to him. If any happened later that night after all lights were out and people gone, it didn't cause the bubble. It was already there. No, I haven't cycled my tank. I honestly had never heard of cycling a tank until you said that-- I'm reading the article you posted right now. Will be getting a water testing kit ASAP.

If you read the articles I posted, you will have no problems caring for your Axolotl.

Also, if you have questions there are thousands of posts on this forum containing valuable information from previous discussions. Just open Google, and search your question with the word Axolotl at the end or within the question, there will likely be multiple pages of threads from Caudata that you can read.

Thank you!

How did this axolotl get on with the bubble on his head?