Posted: Sat Jun 03, 2006 4:35 pm
If the regular light tube is also a flourescent, then it's not giving off enough heat to bask under. You could check the temp by placing a thermometer under it where your turtle would bask (putting the thermometer on an object about the height of your turtle's shell would make the reading more accurate), leave it there for about 20 min. and see what the reading is. You want the temp in the range of 88-90F. A regular house bulb is fine for producing heat (clamp it over the basking area next to the UVB light. Since the UVB light is a tube, you want to position the fixture as much over the basking area as possible.
What kind of UVB light are you using? The strength of the UVB rays emitted by the light drops dramatically the further away the light is from the turtle, so to get maximum benefits, your turtle should be basking under it. If you're using a Reptisun 5.0 tube, for example, having the light about 6-8 inches from your basking turtle would be good.
Sunlight can penetrate water a few inches down, but with a UVB light (much weaker), this would obviously be much less, if at all.
"You become responsible, forever, for what you have tamed." -Antoine de Saint Exupery-