Do I need to be a member to take water exercise classes at the Rockville Swim Center?

I have a question do you have to pay

No, you don't need to be a member but there is a fee. The fees vary depending if you are a Rockville resident or not.

No. But, you still need to pay the swim pass for every class, as I remember.

Well you will need to pay for a swim class or if you just wanna go there to swim you just pay a little fee.