'Lotl stressed because of new tank mates?

Hey all.
I've had Smudge since this past winter. He was alone in a 10 gallon tank.
As he got bigger I bought a 40 gallon and after it cycled he was placed in there.
I then got two juveniles which were in a divided 10 gallon.
As the juveniles got bigger, I divided the 40 gallon, put Smudge on one side, and the two juveniles together on the other.
They were like that for about a month until the young ones caught up in size.
About a week ago I removed the divider so all 3 were together. There were no nipping issues.
However, I haven't been able to get Smudge to eat in the past 4 days or so. His diet hasn't changed- one red wiggler a day, maybe every other day if he's not hungry.
My younger ones are ravenous and they're all looking healthy, although Smudge just isn't interested in eating. (I tried some pellets too).
He might grab the worm, fight with it for a moment and then spit it out, not wanting to try again.
I don't know what could be bothering him other than maybe the new tank mates. Though they all hang out next to each other, and there hasn't been any obvious issues. He's always been really chill and not much of a swimmer, so there isn't really a way to determine if his behavior is different.
Also, not sure if this is related, but he's in the process of re-growing a gill that he lost most of due to a fungal infection a little over a month ago. That seems to be going well.

I have nightcrawlers to try giving him, but I'd have to chop them up GOOD as they are PLUMP and my 'lotl's are only around 6.5 in, and small in stature.

If he doesn't eat the new worm today, should I be worried?

The water got a tad cloudy recently, I'm assuming ammonia is a touch high as my impeller in my filter stopped working--it's been replaced and filter is back up and running, and a water change was done.

I'm not too worried it's a water issue, as my other 'lotl's aren't showing any signs of stress, I'm more assuming it's the tank mates. There is plenty of places to hide, although they all usually hang out in open areas, haha.

Photos attached: Smudge is the black one, with each of his new tank mates getting along peacefully. Sorry they're poor quality pictures with obnoxious glass reflections.

Anyone have any insight? Thanks.

UPDATE:

Just had feeding time, chopped an earthworm up, gave a small chunk to each axolotl. The young ones gulped it up no problem, while Smudge grabbed it once, fought for a moment, spit it out and started twitching/flailing for a moment. He wouldn't try again.

I looked through the top of the tank, and in comparison to my other axies, he's really thin.

You should really test water, not just assume it is OK cause other axies are doing better.

If your impellor stopped working then some or most of your beneficial bacteria will have died. You need to test your water.

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Did a water test.
Ammonia 0.5 (touch high, as I suspected)
pH 7.6 (also high)

I had a feeling ammonia was high because of my filter issue, and as I stated before, I've already done a water change, and will continue to do them daily until it's back where it needs to be. I also added a little bit of aquarium salt to help it along. I'm not too worried about bacteria in the tank, as I've got a few moss balls in there. Although I do have a bacteria supplement I could put in if you guys think I should.

I own some pH down, but I remember reading to never try balancing ammonia and pH at the same time, it could be disastrous, so I'll hold off on that until ammonia is in check...?

I don't own a master test kit, so I can't get Nitrate and Nitrite. Unfortunately I spent most of my paycheck on an emergency vet visit for my bird, so I can't afford one until my next check, which is in 2 weeks. Or I'll have to find time in my busy schedule to run a sample down to Petsmart, as they offer free testing.

I still have a hunch it isn't a water issue though, as my poor guy was in much worse conditons when my cycle crashed and I didn't realize it. Honestly, the levels he was at when that happened, I was surprised he wasn't dead! But he was completely fine. So the fact that he's not eating now makes me worry it's something else

If I get readings for ammonia or nitrite I stop feeding (my fish) until they are back at zero. That way the bacteria get to clear the toxins before you add more. And, of course, you'll get a little nitrite spike following the ammonia reading. Maybe your axie was harmed permanently by the last incident even if it didn't show. Or perhaps he's just more susceptible if he's been bullied. Perhaps the others chase him away from the food? I don't understand why you have used aquarium salt; I understand that some tropical fish benefit from it, but I didn't think axolotls did?

I think, on balance, I would be tempted to remove him to a tank on his own in a dark corner, with cool clean water, a hide and some floating plants, and do large water changes daily. Back to basics, so to speak. I'd be keeping an eye on your main tank, too, as the ammonia will not be good for the others. Perhaps daily 20% or even better, twice daily 15% water changes to lower the ammonia and nitrite, and less or no food until its back to zero. Better hungry than poisoned!

Hope he's better soon

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wandering said:

If I get readings for ammonia or nitrite I stop feeding (my fish) until they are back at zero. That way the bacteria get to clear the toxins before you add more. And, of course, you'll get a little nitrite spike following the ammonia reading. Maybe your axie was harmed permanently by the last incident even if it didn't show. Or perhaps he's just more susceptible if he's been bullied. Perhaps the others chase him away from the food? I don't understand why you have used aquarium salt; I understand that some tropical fish benefit from it, but I didn't think axolotls did?

I think, on balance, I would be tempted to remove him to a tank on his own in a dark corner, with cool clean water, a hide and some floating plants, and do large water changes daily. Back to basics, so to speak. I'd be keeping an eye on your main tank, too, as the ammonia will not be good for the others. Perhaps daily 20% or even better, twice daily 15% water changes to lower the ammonia and nitrite, and less or no food until its back to zero. Better hungry than poisoned!

Hope he's better soon

Sent from my Nexus 7 using Tapatalk 2

Click to expand...

I don't know if he would have effects of the cycle crash now, as that was months ago when I first got him in the winter, and he just stopped eating a few days ago. He hasn't been bullied as far as I can see, and they're in a common area of the house so I see them interacting a lot. I know they don't chase him away from food, either. I sit and observe feeding time just to be sure of that. I also wasn't sure about aquarium salt until a few people on here told me to do it after my cycle crash incident, so it's fine for axoltols. I might still try quarantining him, but I'm not sure if I'll be able to keep up with it because I am CRAZY busy this next week, a lot going on. And my cousin just moved in, so we're tight for space for another tank. I'll see what I can manage though, I love my little guy and want him better.