Is my axolotl feeling alright??

Hi everyone! I got an axolotl in January from an exotic pet store. He's my first axolotl so i just want to make sure that everything's going alright. I'm not sure how old he is but i know he's old enough for me to properly tell that he's a boy.
Basically i have two concerns:
- his eating habits
- his activity level

When i first got him, i immediately started feeding him earth worms because thats what i was told would do best for him. He tolerated earth worms for about a month and then stopped eating them. When eating them, he would kind of fight with them? Like he would vacuum them into his mouth and then it would fight to get out and he would spit it out and try again but now he'll take it into his mouth once and then immediately spit it out. Since then, I've been trying to make sure he has a varied diet so he doesn't get sick but i wasnt prepared for him to deny worms so i need to make sure im feeding him right.

Right now his daily meal is one cube of bloodworms and one cube of brine shrimp. He eats it all but I'm worried that i'm not feeding him right or feeding him enough.

Onto his activity level, i'll start by saying i know axolotls aren't super active and my worries are mostly based on the fact that i know he used to a bit more active than he is now. He used to play in the bubbles from his air stream and run around the tank every day but now he hardly does that? Generally he just hides under one of his plants in the back of the tank.

His tank parameters, tested right before i post this, are as follows:
Tank size: 20 gallon long
Ph: 7.6
Ammonia: either none or very little
Temperature: 66 degrees F
Substrate: fine aquarium sand


Tdlr; how much should i be feeding my axolotl, why won't he eat worms, and is it okay that he usually just hangs out all day and doesnt do much

The earthworms may be too big for him to eat. Would you be able to cut them up (I just can't... <shudder/>)?

I feed my adult axolotls salmon pellets and sometimes Hikari Carnivore sinking pellets about every 2-3 days. Maybe yours is just not that hungry? For an adult, I don't think bloodworms as the staple food item is enough. Also adult brine shrimp are fine to feed occasionally, but I have been told more than once that those are 'junk food' for aquatic pets.

Your axolotl hanging around most of the day seems normal to me... None of my adults are ever extremely active. They usually just wander around occasionally throughout the day! Your water parameters seem fine too.

I hope you new pet continues to do well in your care!