Appetite and behavior change

[BMM22]

I've got four small-mouth salamanders (A. texanum) that I'm concerned about. I raised the little guys from tadpoles and now they're just over a year old and around 2-3 inches long. Things have been going fairly well up until now. For the first year or so, I kept them paired up in some plastic containers that are about 8x4 inches big. Moist paper towel seemed to work fine as a substrate and I gave them some slate rocks and fake plants to hide under along with a small water dish. They seemed fairly happy and I haven't had many issues with them eating since they left the water. They have slightly different personalities, some eating with more gusto and some more shy, but I've never had any of them skip more than one feeding without eating. Their diet is mostly frozen bloodworms with the occasional earthworm thrown in. I use calcium and vitamin powders since I know bloodworms aren't sufficient on their own. Due to how big they're getting, I made the decision to switch them to a bigger setup about a month ago. I have a 20 gallon long tank (30x12 inches) that seemed like a good size for the four of them, so I put about 2 inches of coco-fiber in that along with a bunch of slate rocks and two water dishes. I use a partially covered screen lid and mist it daily. Things seemed fine at first. They quickly took to digging and I would occasionally catch them soaking in the water dishes. However, it seems like with every passing week they're getting more lethargic and eating less. It's to the point now that I never catch them above ground and I'm lucky if I can get more than one of them to eat each feeding. They don't look like they're losing weight yet and there aren't any physical signs, but I'm really concerned that something with the new setup is affecting them negatively. Does anyone have any ideas or suggestions? I'm to the point where I think it would be better to move them back to their old setup.

 

[Herpin Man]

When you say "lethargic", do you mean more secretive? If so, that is normal. What have you been feeding them in this new enclosure?
I suggest size-appropriate earthworms, isopods, dubia, crickets, etc. I also suggest not looking for them or digging them up unnecessarily. Mist the plants in the evening, and you may see them active after dark. This is also a good time to feed them.

 

[BMM22]

I only dig them up to feed them, which is two or three times a week and I put them in a separate container when I do just to avoid any potential impaction issues. I'm still feeding them bloodworms and occasionally small worms. Due to their size and their species, things like isopods, roaches, crickets, and the like are simply too big to feed them. In their old enclosure they would get excited to eat, usually watching me the whole time and lunging for their food. Now they just sort of sit there and when they do eat it's only when I dangle it directly in front of them. It feels like their energy levels have really plummeted.

 

[Herpin Man]

The process of digging them up to feed them could be enough to inhibit feeding response. My suggestion is that in the evening, mist the enclosure, dump the prey items in, and leave them to hunt on their own.
The low energy isn't necessarily an indication of illness. However, this time of year, overheating may be a concern. They should be kept in the coolest part of the house.