1. Yeah, you could keep the frog on paper towel but it might be a little stressful for him.. you should atleast throw in a hide or a fake plant for him to go under. It doesn't cost very much to get some Coco Fiber, which is the best substrate for them.
2.The white liquidy substance in the water? I'm not sure what that is. Sometimes when they go in the water after shedding they'll leave some skin floating around, this is kind of gel-ish, it's just usually the color of the substrate they've been in.
3. Only male Pacmans croak, as far as I know.
There are far more experience frog keepers than me here and I'm sure you'll get all the information you need. Also, don't feed your Pacman goldfish as they carry parasites and you don't want those in your frog. Nightcrawlers make a great staple diet for Pacmans and they love them. Hope this helps.
EDIT: Welcome to the forums!![]()