My 6 Month Old Axolotl Isn't Growing??

I first got my axolotl when he was first in his egg, he hatched on the 16th august 2010 I had six but he was the only survivor, the others didnt eat:/ but this was never a problem for him. My brother also has an axolotl and his is the brother or sister to mine. I have noticed that my brothers has grown rapidly and is now very big! but mine seems to have hardly grown, he eats properly, the waters fine, he has loads of plants, he eats dried bloodworms,he has sand a filter a light. he alos has a great personality, whenever i'm looking into the tank, he will turn his head and watch me put the food in, and he will let my hand feed him. but I just don't know why he won't grow, i have asked this before and someone said he might have a form of dwarfism, can anyone confirm this or give me any other reason??
Thankss

i have also attached a photos of him or her that i took about 5 minutes ago

You should try feeding him more nutrient filled foods. I don't think dried bloodworms can support a growing axolotl. Try giving s/he frozen bloodworms instead. If you can find them, live black worms are perfect for little axies and are one of the best foods you can give them. I would try this and see if s/he starts growing more. Axies, even brothers and sisters, grow at different rates due to genetics. Feeding them food high in nutrients also helps.

Also, very cute little face!

Freeze dried bloodworms are almost totally void of nutrients. I'd bet that is attributing to his lack of growth. Dwarfism is pretty rare. Try defrosted frozen bloodworms or small earthworms and see if that helps spur some growth.

It might be worth putting the little guy into a smaller tank with live food. He might struggle finding the food in such a large (lovely ) tank.

Since you are UK based live blackworms are not an option as there are no UK suppliers. I used chopped earthworm or small whole earthworms at this sort of size. I also tried feeding in a small container and waving worms with tweezers under the axolotls nose!

On the whole the chopped earthworms in a small container will probably avoid a mess in this lovely tank.