I just use batu-bata for the turtles to sun-bath. Hehe..
Btw, here's an update of my pet turtles, Obi and Kenobi. Since they are getting bigger and I figure out that they may not be comfortable living in the third aquarium I bought [red cover as in their PF profile], I've transferred them to a new tank. And btw, this year is their second year living with me... healthy as always :)...
Bought them in March 2009 - almost 1 month old
March 2010 - 1 year old
January 2011 - 1 yr 10 months old
Their photos below:
-SEE ATTACHMENT