Fire bellied newt's back legs have stopped moving

[jakedesalvo]

Hello. My little friend has been acting strange for the past two days, looking like he was having trouble swimming and kicking around a little. I woke up today to see he's got his back legs turned in towards his tail and he doesn't appear to be using them at all. He lives alone and nothing new has been introduced to his environment the last few weeks, and I'm a bit concerned. Here's a view of the back legs. Does anybody have any input?

 

[jakedesalvo]

So I wrote the post before doing homework, as a knee-jerk reactionary caretaker of a living thing is likely to do, and I've since been reading about a ot of similar issues here. Mostly it sounds like this is caused by something impacting the digestive system, but I'm not convinced that's the case here. There's no bloating and his boring diet doesn't get a lot of variety. There was also the guy whose pet had a tumor impacting the spine, but I'm hesitant to call that the culprit so early.

So my question is: Can something like this be caused by factors in the environment? I've had an algae problem for a month that I'm having a great deal of difficulty controlling, and I'm not sure of the state of my water lately. I'm stumped and just spitballing, really. Most of the forum posts don't have any follow-up, so maybe I'm freaking out a bit.