Help, is my axolotl okay?

[Jesi]

I just picked up Benni from his previous owner a few days ago along with his established tank. I’m not super worried about my water parameters as they are all looking great, but I am a little worried about his size.
His previous owner told me was about 18 months old and that he has failure to thrive and will not grow any bigger. I’m not super convinced about this because what she told me is she has been feeding him only blood worms because of how small he is and from what I understand blood worms don’t have much nutritional value. I plan to feed him primarily pellets from now on.
Does anyone have experience with an axolotl with failure to thrive? I want to make sure I am doing what is best for him!

 

[wolfen]

would it be possible for an overhead photo.
even though the tank is established the parameters will need monitoring for a while to make sure the move went smoothly.
add an air-stone into the tank (if there isn't one)
add 2g/l non-iodised salt or if possible 50% holtfreters with 0.1g/l magnesium sulphate (preferable), this will provide optimum water chemistry whilst encouraging gill and over all growth.
although feeding only bloodworm isn't a very nutritious diet it won't cause a stunt in growth.
feed a varied diet which includes food that contains vitamin A (eyed food contains vitamin A ie.. fish, shrimp, krill etc.., non- eyed food ie.. worms etc.. don't contain vitamin A, lack of vitamin A is associated with a failure to thrive)

 

[Jesi]

would it be possible for an overhead photo.
even though the tank is established the parameters will need monitoring for a while to make sure the move went smoothly.
add an air-stone into the tank (if there isn't one)
add 2g/l non-iodised salt or if possible 50% holtfreters with 0.1g/l magnesium sulphate (preferable), this will provide optimum water chemistry whilst encouraging gill and over all growth.
although feeding only bloodworm isn't a very nutritious diet it won't cause a stunt in growth.
feed a varied diet which includes food that contains vitamin A (eyed food contains vitamin A ie.. fish, shrimp, krill etc.., non- eyed food ie.. worms etc.. don't contain vitamin A, lack of vitamin A is associated with a failure to thrive)

Here are the best photos I have of him while he was tubbed for a short time, I was told that his belly sticks out to the side after he eats, but I’m not sure why. Do you know why this would be?

Also can I feed him brine shrimp that I grow from home? Or do I need to buy them from someone already grown?

 

[wolfen]

due to size/age he/she will bulk out at the sides after eating, this is due to how the intestines sit and is normal, as he/she gets older it will become less noticeable.
brineshrimp are fine home grown although as he/she gets older using frozen might become easier due to amount required.