redearslider.com

What do you guys think of undertank heating pads? Are they effective in heating water? Or are the submersible ones the best ones to buy?

Also, I have a 10 gallon tank and am hoping to upgrade to something larger soon. If I got, say a "up to 30 gallon" heater, would that be too much?

Submersible heaters are the best way to heat turtle tanks. I don't believe undertank heating pads are meant for aquariums.
Submersible heaters should shut off when the selected temperature is reached in the water so a slightly larger heater should be ok, you'll probably have to play with the setting a bit to get 78 degrees though.

If I may offer a suggestion on the upgrade, you'd be wise to upgrade to as large of a tank as you can afford. A 30 gallon tank will get you through the first year but not much farther.

Electricity and water really don't mix - unless the wiring is definitely designed for a wet environment (like in the case of a submersible water heater), don't use anything electrical around your tank where it might get wet.

I bought one of those heating pads, and before unpacking it noticed that it said not to use it with aquariums. Stick with a submersible like the Visitherm Stealth heaters, many people here like those.

Go with submersible....the undertank heating pads are made for dry reptile tanks (like for iguanas & lizards).

One more vote for submersible... the under tank heaters are not designed to take the extra weight of the water.