Need help with Skinny Male

Hi All,
Need some help/suggestions with this male. I have posted pictures of the pair & the setup. The female is plump and feeds well. The female swims around and is fairly active. The male seems to move about quite a bit, but I have been concerned about him, since he seems to have lost weight. I have them in a 30gal tank with a rock formation along the back of the tank. Water is temp is usually around 70 deg F/21 deg F. However I checked tank tonight and water temp is at 62 degrees. I have a finished basement and I keep all the newts here. The room temps bounces between mid 50's to high 60's. All the other newts, 3 Eastern Newts(Noto. viridescens), a pair of Tylototriton Shanjing, a pair of Kwiechowensis and a pair of Triturus marmoratus are all eating and doing well and are fed the same foods & keep in same room.
I feed these guys crickets, orange isopods, wax worms and cherry shrimp & scuds are in the water. I also feed them live glass worms, black worms & daphnia, frozen blood worms by Hikari.
I have recently isolated the male in a rubbermaid bin with coco fibre, cork husks for hiding places & a small bowl of water. Then added ispods, spring tails & 1/8 size crickets. So this way he gets all the foods.
If anyone has any suggestions please let me know.
Thanks,
Ed

Other than indeed isolating and keeping an eye on him, I have no suggestion. But how is the male doing now? Any signs of improvement?

The poor thing looks pretty bad....
The skin is starting to look a bit weird, so i´d suggest that it might have a bacterial/fungal infection (although it may not be the original problem).
How long have you had them for? and are they WC? If they are, there´s a possibility that the animal is succumbing to parasites, or any illness that it might have carried or acquired during the importation. WC kaiseri are known to develop problems in captivity...that´s why i mention it.

This may be a weird suggestion but have you tried smelling it? I've had animals with bacterial infections that smelled weird. Try to compare the smell with other healthy animals. Be sure to clean your hands after handling the sick animal though, you wouldn't want to transfer any diseases.