Shrinking gill feathers?

My wild type who has always been a runt, has never eaten as much as my other axolotls his age, and he's never been as active as my other axolotls. That being said, I've always given him special attention, made sure he ate enough, etc.
He is in a tank with my leucistic, who is super healthy, normal sized, eats great, and is super friendly with him, she's never nipped him or anything like that.
The water parameters are great, I do weekly water changes with seachem prime, water is at 66 degrees, they eat blood worms and some pellets every now and then. We just moved about a week and a half ago to a new apartment, his move was very easy going I put all of their tank stuff into a big bucket with their tank water and then put them in there and an ice bottle, brought them straight over, set the tank back up with seachem prime and got them back in within a few hours.
His gills are shrinking away, they almost look like they're rotting off.
My leucistic that is with him has beautiful healthy gills, so I don't think it has to do with the water. I'm not sure what it is. Pics are of his current dead gills and his old gills for comparison.
Is he going to be okay? Is there anything I can do to help him? Is he doomed?

Hes probably lost them a little due to stress, which is whats happened to my little one before. Keep his parameters and temp at check and they will grow back - they're good healers

When they lose their filaments it's usually a result of something being off with their environment. Strong water currents and temperature are two of the common causes.

How are you keeping your tank cool and what type and size filter are you using?

Elise said:

When they lose their filaments it's usually a result of something being off with their environment. Strong water currents and temperature are two of the common causes.

How are you keeping your tank cool and what type and size filter are you using?

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Keeping it cool with a small fan, filter is a 10 gallon hob filter on a 15 gallon tank.

Have you been testing for ammonia after the move? Just incase it affected your cycle? It looks a lot like something I saw on another forum and that was because of ammonia.

keiko said:

Have you been testing for ammonia after the move? Just incase it affected your cycle? It looks a lot like something I saw on another forum and that was because of ammonia.

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Yeah, I've been testing daily. It hasn't been going up.

Jonjey said:

Yeah, I've been testing daily. It hasn't been going up.

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whats ammonia at right now?
post all your water parameters, ammonia, nitrite, nitrate, PH, temp

mine started losing bits of gill as well, turns out he liked to swim by the HOB filter and his gills would get sucked in and then ripped off when he swam away
I put a bit of sponge over it and theyve grown back nicely

Have you tried them on earthworms? Good nutrition is key to regrowing the gills, and worms are a great balanced source of nutrition for axies, not to mention cheap (grow your own) and clean (don't soil the tank).