I agree with Grif, the dark coloring is not a good sign. Has he been eating, acting lethargic, or just sitting in his water? Are his legs red because in the picture they look a little like a disease called Red Leg, ( it may just be the frogs skin coloration of it is pinkish because my baby's skin is that color) If it happens to red leg then I would call a vet. And yes go ahead and put him in a desperate container and be sure to monitor your other baby to make sure she has not caught what her brother had. I hope Lawrence gets better