Greetings to you Chris! Good to hear from someone who loves his turtles! Do you have pictures? We'd love to see them.
Read up on the general information on this site. Here's a link to start with:
http://www.redearslider.com/index_basic_care.html
Then, look at the stickies posted at the top of each section of the Forum. Lots more good info there.
One thing you're going to find is that 30 gallons is probably too small for your three beasties. The rule of thumb is that you should have at least 10 gallons of water for every linear inch of turtle shell - measure from the front of the shell to the back of the shell without counting the curve in the shell. This rule of thumb is especially important in a multi turtle setting because if there's not enough space they will compete and the big ones will pick on the little ones. They can really hurt each other. Sometimes this happens even when there's plenty of space - it just depends on the personality of the turtles!
You might double check on the gender of your little hatchlings, too. No one can really tell the sex of a RES until it's shell is about 4 inches long and it's considerably older than a hatchling. You'll find many threads on here from people who get a surprise when their little girl or boy grows up! Someone may have told you you have a girl and a boy but they don't really know.
Anyway, welcome and good luck!
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