Sascha K.
Google
First of all: if you rent towels or swim suites, keep the receipt for that, otherwise you'll get into trouble when it's about getting deposit back. The guys at the entrance won't mention that probably.
Sauna is ok, but many tourists who don't know how to behave in a sauna and the "water on the hot stone" procedure (Aufguss) is automatic. Means, not really satisfying.
Pool is 15€ and that's not worth it. If you go there, take the sauna + pool choice for about 22€