Frog Lethargic, Discoloured and not eating.

[BlueKiwiOca]

Checked on Treecko tonight and he seems to have taken a turn for the worse... Did a poop but it was badly formed and smeared everywhere, saw some undigested fruit flies. His rear end was reddish, possibly bloody. And most scarily, his skin is very discoloured. I'll attach a photo of him a couple of days ago, and then tonight

[BlueKiwiOca]

Bumping this. Treecko died the night after I posted the last update, and now I have another frog who seems to be sick with the same thing. After Treecko died I cleaned out the terrarium thoroughly, and replaced all the sphagnum moss.

Froakie has been very dull-coloured and lethargic as of a few days ago. He had a weak feeding response yesterday, and none today when I offered him fruit flies. I've now isolated him in a hospital tank. Help please?