Illness/Sickness: Axolotl eating very infrequently, possibly bloated or impacted?

My friend and I bought two axolotls on April 2nd, they're just under two inches I believe. They are unable to house theirs at the moment so I am holding them both in a 10 gallon tank I had kept running with live plants after rehoming my fish (it has been thoroughly cleaned). Ammonia, nitrates, nitrites all read zero and their tank stays a steady 63 degrees. I just got a fan to set up to blow across the surface of the tank so hopefully that brings it down a couple degrees.
Both axies are active and interested in food, but the leucistic one doesn't always bite with enough force or enthusiasm to eat. They open their mouth but don't suck in any water, and when they do snap they usually spit out their food. I spend a lot of time wiggling individual bloodworms in front of them to get them to eat even just three or four. Just today they seemed to have formed lumps on their sides and look like they may be a little bloated? They seem very skinny for their size so I wonder if the lumps are just food because they seem to be moving around their body.
I also found a piece of gravel in the tank this morning which definitely was small enough for them to swallow, I don't know what axolotl it came from but it was not originally in my tank so I think that one of them may have passed it. We don't know what conditions they were living in before we got them. The leucistic one has a dark circle in their chest which could just be guts or food but I am unsure and worried it could be another rock. They pooped while I typed this and were receptive to live brine shrimp yesterday (well rinsed), I'm going to continue to try and feed them live foods with some frozen bloodworms.
I attached some pictures from earlier and two I took today. It looks like, from the pictures, that the black dot is moving around in their body so that may have been a rock? If it is, I have only ever seen the one. I can't find any clear answers from looking at other pictures of baby axolotls.
During the time I wrote this the lumps seemed to have gone away? It may have been food or maybe even air bubbles but I think its still worth leaving in this post.
I am very new to caring for axolotls and I have looked up as much information as I can on this but I cant find any information relating to these circumstances, and getting confirmation is always helpful! Thank you for reading, I hope we can figure this out and get this little guy eating again.

If the wild type is eating fine and acting fine it may have been the leucy who was impacted and passed the gravel. Keep with the live foods. Give black worms a try if you can get a hold of them. They are small and very wiggly so they may be enticing. Hopefully a senior forum member will give you a better idea. Best of luck

I am trying to get a hold of black worms but my LFS is out of them at the moment. But the leucy seems to love the shrimp and an hour after posting this I tried to feed them and they ate more than I've ever seen them eat!
I am beginning to think I was overreacting a little in rushing to make this post considering what I thought was bloating has gone down a lot but I'd rather be safe than sorry. It might have been just the very beginning of symptoms that could have been much more serious if they hadn't passed the gravel last night/early this morning.
Thank you for your reply anyway! And best of luck to you, too.

Hi there and welcome to the forum. :happy:
Congratulations on your new pets, they are lovely. Don't worry about panicking, we all do it when it comes to out little ones.
I have only been keeping axolotls for less than 2 months, and I have 2 leucistics, 2 wild types and 2 coppers. You will be able to see the internal organs & food in your leucistic, and that is normal. Looking at the pictures there is one darker patch, which may be food or something else, so keep an eye on that. If it is gravel hopefully it will be passed soon.
Hopefully one of the more experienced keepers will offer some advice. :happy:
Please keep us posted on your progress.

Would it be advantageous to get a breeder box to house them in for a while? I have seen ones on the larger side at my LFS and it seems like it would be useful for me to watch what they're passing more closely. I find a lot of poops in the tank in the morning but obviously I can't tell who its coming from, and the pink one floats around with their tail higher than the rest of their body a lot of the time, but ive never actually seen them poop... They can still land when they want to, or within a minute of wanting to, but I still worry.
You can also barely tell in the photos I posted, but their gills started looking much less feathery over time. When we first got them they seemed to be almost stuck together but over time they fanned out and disappeared. I didn't even notice, I was spending more time making sure they were eating and their water was clean. They seem to be growing back very slowly now after comparing all the pictures I've taken and how they look today.
Sorry for asking so many questions! I am an extremely paranoid person, haha. I suddenly got it in my head that my wild type is actually a tiger salamander and ive been comparing them to pictures for most of yesterday and today. But anyway, thank you all for reading!

I just want to check on your tank and water parameters. Early you said that they were all 0. Is your tank fully cycled, or have you started testing the water when you got the axolotls? I'm a little concerned as going off food and starting to lose gills may be a sign of a bacterial infection, which is usually caused by stress or poor environmental conditions. Obviously, as you have not had them long, the move from breeder to your tank may have caused enough stress. If this is the case then usually excellent water conditions will help as your little ones heal themselves. :happy:
Axolotls - Health & Diseases

Ingested gravel could be the lumps you were seeing, I wouldn't be surprised if more is passed, it can take months for Axolotls to full pass gravel in their system.

You need to make sure your tank is cycled, your test results show that it is not. Cycling is needed to allow a nitrifying bacteria to colonise your tank which will feed on ammonia and convert it into nitrite, and nitrite into nitrAte. Ammonia is produced from your Axolotls waste and degrading food, ammonia, nitrite, and nitrAte are toxic to Axolotls so cycling your tank to produce the beneficial bacteria is needed. The bacteria will feed on the ammonia, and nitrite, but once converted to nitrAte you must perform water changes to keep the nitrAte under 40ppm so it is not at a high level of toxicity.

Cycling is one of the key factors of keeping your Axolotl healthy. Healthy tank water prevents fungus, disease, and stress.

Read these articles on cycling:

Caudata Culture Articles - Cycling
Caudata Culture Articles - Water Quality
How to Cycle a Fish Tank

If your tank is not cycled, I would recommend moving your Axolotls into separate containers and perform 100% daily water changes with dechlorinated water. Purchase liquid ammonia to use as an ammonia source to keep feeding your tanks cycle.

My tank is cycled, I do slight water changes every day after feeding while cleaning up the mess, which maybe adds up to a 10% water change a day in total, 50% on weekends. I do almost daily tests as well because I transferred my filter media from my old filter to one with a much weaker flow and I want to make sure that the bacteria is doing their job, and that these symptoms aren't caused by poor water conditions. If my tests ever read anything, it's a little bit of nitrate. I think when I brought the lotls home for the first time I did a test on my tank and nitrate read about 20, everything else zero, I did a water change to put colder water in the tank and let them loose in it after their cup water was the same temp.
If water parameters are all that seem to be worrying here then I am glad! I do have tubs I can keep them the instant I need to, that was a thing I checked before buying an axolotl.
Thank you for your reply!

Actually, I think I will put them in tubs even though I am very sure my tank is cycled just to be on the safe side. I don't want to take any chances, especially since the one having so many problems isn't even my pet... I'm worried that keeping two tubs at the right temp will be difficult but I have a day off today so I can watch them as closely as I need to.
Thank you again! At the very least, this will make it easier to feed them, haha.