...and testing process to volunteer at the aquarium and passed, but it's too far for me to drive now and too much of my time is spent teaching.
To become a volunteer diver, you take a written test (much like any agency's final OW exam) at the local dive shop that sponsors much of the work at the aquarium. Then the dive shop staff takes you to a YMCA for a buoyancy test. You go through an obstacle course to prove that you aren't going to destroy the exhibits with poor control. If you pass the written test and the pool test, you then go through standard volunteer orientation at the aquarium over a series of nights. It's comprehensive, covering all exhibits, etc. and you must be willing to volunteer in most all areas of the aquarium, not just diving. Once you are through the training, you get started.
And as some previous posts have said, you MUST buy a Mares wetsuit through the aquarium and the dive shop (at cost). Your wetsuit and all other Mares gear (which they supply) is kept at the aquarium and goes through a regular cleaning process. You can't take it with you or use it for diving outside of the aquarium. This helps reduce the liklihood of contamination of the exhibits.
It's not too tough to get into the program, and it seems like fun. Places like the aquarium are almost always in need of assistance, so I hope you will go through with it. I wish I had more free time so I could join in.
Safe diving.