There is definitely a learning curve we all have when keeping pets. It doesn't help that pet stores often have no idea how to keep the animals they sell.

Having a cycled filter is definitely a plus. I keep two 5 gallon buckets filled with cycled K1 for aquariums. One for saltwater and one for fresh. I add ammonium chloride once a week to feed the bacteria. I haven't tried it for frogs yet because I think the clicking caused by the media would be annoying for them.

You will do great with this guy. Like Jen said, any questions, just ask. There are lots of good people here ready to help.