J.L.
Hi K.,
My husband and I joined when our little one was only 6 months old. We joined the Palm Harbor Branch, but check this link, I beleive you can use your membership at any of the YMCA's of the Suncoast. If you cannot afford the membership they have an "open doors policy", no one gets turned away.
We enjoy it because of the excercise room and our little girl loves the kids zone! The pool is very refreshing in the summer too!
http://www.ymcasuncoast.org/
Have fun,
J.