Plants in a turtle tank

Its a RES. An above tank basking area just isn't an option right now so I'll have to have some space near the top for a basking area. Whats the minimum distance away from the basking light that the turtle can be without getting too hot? ..That will have to determine the water level that I'll be able to use.
 
If you have a clamp light for the basking light, you want it the right distance to keep the basking area around 90 degrees. You can get it within a few inches of you use something like a 30-40w bulb. For the UVB, you want that as close as possible because for most lights on the market, their effectiveness drops very quickly as distance increases. They also don't penetrate water very well so the only effective exposure they get is while basking.
 
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