I suspect others will get more heat out of it. As I said, I went with the 160 watt, which has a minimum distance of 18". I have it at 21.5".
The tank is in the basement. Temps at night are dropping into the 40's and we have windows open. The air temp there is probably around 67 degrees.
My basking area is pictured in some of my early threads. It's an acrylic ATBA with two 6"x6" pieces of tile. The whole area is about 12"x8".
I ordered sometime in August. Call it seven weeks for delivery.
Tobi hasn't shed since March. I wouldn't say I have pyramiding, but there are definitely layers of retained scutes. I suspect UVB is part of that. I've tried blueberries and koi pellets with wheat. In researching UVB, I ran across quotes from a 2012 freshwater turtle research paper that's paywalled, so I can't read it. There is apparently a quote there from a 1996 research paper I can't find online that says:
Signs of MBD, shown in adult freshwater turtles, include “progressive mineral loss of the shell, shell
and endoskeleton fractures, pyramidal shell growth, egg retention and concurrent hypovitaminosis A
(Barten, 1996)”
I found that on a blog that appears to be from a high school student doing research on sea turtles. I wish there was contact info to thank him or her.
http://seaturtleresearch.weebly.com/basking.htmlBut that combined with what I've observed in wild turtles in the area leads me to believe that the online recommendations for RES UVB exposure may be on the low side.
I love in NW Indiana, near Chicago. The entire area was swampland that was drained for settlement. There are numerous ponds with RES, painted turtles and snapping turtles. It's also at the extreme Northern edge of the natural RES range. Driving my car, walking the dog, even in a pond near work at lunch, I see tons of RES and painted turtles basking. When I got the SolarMeter, I was reading 350 at noon, and there are turtles basking then.
Since most of the RES range is south of me, know the UVB will be higher. I know too that the UVB is much lower throughout most of the day, and there are cloudy days when the UVB is minimal or nonexistent. But I have a hard time believing that the types of recommendations online aren't on the low side.
So, once Tobi starts basking regularly under the new UVB light, I plan to watch her closely, but right now I feel like I'm providing something she's been lacking for some time.