What is wrong?

[Fred the axolotl]

Hi, my daughter has had this little axolotl since Christmas time so I’d say it’s around 9-10 months old. It’s been floating at the top of the tank a lot and I think has possibly struggled to get its food. I’ve been feeding with tweezers now for about 5-6 days and it eats and now is spending more time on the floor of the tank. I sent a photo to a Facebook page asking a question of sex and someone commented that they couldn’t tell as it was under weight and had a possible bacterial infection. What would I do to combat these two issues…I have frozen blocks of food and it would eat 1/2 to 3/4 a block - day.

 

[wolfen]

what are your water parameters ie.. temperature, ph, ammonia, nitrites, nitrates, if possible kh and gh.
your axolotl does look underweight but without seeing a photo from above can't say for definite, the torso should be same width as head.
ensure adequate oxygenation of the water, do not feed any type of hard pellet (if hard soak them first), if he/she will eat a whole block of food give him/her a block, if he/she will eat two give two, the feeding can be reduced once up to weight.
the tail is slightly pink/red but without seeing the parameters can't say if sign of infection, same as requiring closer view of head/gills, house him/her in 50% holtfreters + 0.1g magnesium sulphate, info here.. Axolotls - Requirements & Water Conditions in Captivity
as to gender he/she is too immature to tell, possible female although could be immature male.