Lighting

[Tortellini]

Hi, I am new to this forum and also have concerns about lighting.  We have two baby Russians about 4 mos old.
We currently use a vivarium that is approx. 30" long x 12' wide and 14' high.  We use two round clip on lights.  A UVB is clipped on at one end of the vivarium above the water and food; the 50 watt basking light is clipped over the center; and then the hut and burrowing strata are at the opposite end from the UVB.  At the basking area the temp is 90-95 degrees. 

We keep the UVB light on for about 10 hours per day.  The basking lamp heats the area very quickly and my concern is that there is not enough differentiation in temperature because we are working with a total length of 30"
These little guys are so small -- I do not want to cook them.
How much heat and how long should we keep the basking light available?

[AW1971]

Hi, i suppose everyone has different opinions. I`m no expert but i`ll tell you mine and it seems to work so far for me. (I have 2 horsfield tortoises aswell)
I use my house central heating as the background temperature, i have a large guinea pig cage (4ft by 2 1/2ft). I went to town and bought the best cage i could as i only keep two, (cage each) i would have to get a cheaper set up if i had more.  It`s great because it has a wire roof so i hang my lights off at a desired height and i`ve made a second floor at one end. The uvb is 6 ins from floor and covers the basking area through to the other end but stops just before the cooler end with the bedroom. I have blankets on top which keeps the heat at a steady 80 ish. My 60watt basking bulb is in the left corner over a piece of slate which warms up (6 ins high), i keep that area flat as i have young horsfields like you and its so easy for them to tip up. The middle is like a play area with plants and rocks and bark to climb on. Then in the far right corner is an enclosed box (removeable lid on ) which my tortoise can get to by climbing up a ladder (high sides for safety). Dinner is fed on a piece of slate covered in calcium which i take out after an hour, this way it keeps the house clean. (I`m fussy like that, lol).
I can`t mix my tortoises yet as one is recently aquired and tiny compared to the other one, but i`m sure yours are very happy together. My basking lamp comes on at 7am, my uvb comes on at 8am. They get up then. The uvb goes off at 11pm, the basking goes off at midnight. Then i close up the blankets and it holds the heat at 60ish all night and they each are buried fast asleep.
Hope you understood some of that i can waffle on sometimes.
Alex

[Joe H]

I have blankets on top which keeps the heat at a steady 80 ish.

What part of the cage is 80°F ?

[AW1971]

Under the basking lamp it`s 95. In the enclosed box at the other end on the second floor i keep it at sixty. In the middle and around the basking area i keep it a constant 80. I did have it cooler around 70-75 but Tefa `s eyes and nose were always running so i warmed it up a bit and alls well.
Seems to work so far, if it`s cooler she won`t get out of bed ,lol.
Alex