When u get a reptile uth they are based on tank size. They have them for most tanks. they will say for 10 and 20 gallon tanks and so forth. Thermostats are a must with all heating sources. Something can happen to the heat source and might get to hot so thermostats are good to have so they shut off the heat source. Here is a good site for thermostats.

http://www.lllreptile.com/catalog/17...ats-and-timers

Here's a site for uth.

http://www.lllreptile.com/catalog/16...able-and-rocks

U can also check your local pet store but this will give u an idea of what to get.