dimmers revisited

A question for the forum: I currently have the lights and infrared heaters in Daphne (russian tortoise's) enclosure on a timer. They click on every morning at 6:30 and turn off at 11:30. There's a CHE that's not hooked up to the timer, so it's on all the time to provide heat without light at night.

The question: I'd like to put the lights and infrared heaters on a dimmer switch, so they don't come on so abruptly. Even if they slowly come on over 30 seconds, it might be less harsh on her eyes.

I looked at previous forum posts about dimmers, but didn't see much consensus: is there a best practice for doing this sort of thing? What are risks that I should look out for?

What type of lights do you have?

The lights are two inrafred bulbs (for heat) and a fairly large LED (for visible light). There's also a UV tube at the other end of the enclosure, but it's on a separate timer -- my understanding is that it's not possible to dim a UV tube (though I'd be happy to be told otherwise)

Infrared lights should not be used over tortoises. They can see color better than we do, and those bulbs make the world look red to them. It messes with their minds.

Unless you live inside a refrigerator, you shouldn't need night heat for a Russian tortoise. If you do, your CHE set on a thermostat to 65ish, should do the job.

I'd replace the infrared bulbs with white, daylight simulating bulbs of the correct wattage for your enclosure. The LED is nice for additional daytime light.

6:30 am to 11:30 pm is 17 hours of daytime. That is too much. 12-13 is good, and no need to ever go over 14. They need darkness at night, and a long enough night, to sleep properly.

I don't see any mention of UV lighting for Daphne. I love that name...


There are four elements to heating and lighting:

1. Basking bulb. I use 65 watt floods from the hardware store. I run them on a timer and adjust the height to get the correct basking temp under them.
2. Ambient heat maintenance. I use ceramic heating elements or radiant heat panels set on thermostats to maintain ambient above 80 degrees day and night for tropical species. You'd only need day heat for a temperate species like Testudo or DT.
3. Light. I use florescent tubes or LEDs for this purpose. Something in the 5000-6500K color range will look the best. Most tubes at the store are in the 2500K range and they look yellowish.
4. UV. If you can get your tortoise outside for an hour 2 or 3 times a week, you won't need indoor UV. If you want it anyway, get one of the newer HO type fluorescent tubes. Which type will depend on mounting height.

Thanks for that! That's good to know about the red lights. (I also think the red looks a bit strange, and I don't have to live under them). I'll replace them. Also good to know about the timing for the lights. Thank you! As long as we're on the topic, I've always wondered: is there a better way to do lights than bulbs directly over their heads? I've always wondered if the direct light is too intense for them.

Heat wise, I'd read that one side of the enclosure should be in the 90 - 100 range, and the other side shouldn't go below 65. I've had a hard time keeping the "hot" side of her enclosure over about 70 with just the CHE. (With all of the lights on, her basking rock registers about 100). Am I overdoing it? She seems to spend a lot of time on her rock, so I assume she likes it. At night, she usually burrows into the substrate under one of her hides, so I figure the soil gets warm in the day, then traps heat at night.

As for UV, we live in Chicago, so there's no going outside for Daphne until May (optimistically) or June (more likely). I have a fluoro tube for UV, which comes on every day; from what you're saying, though, that's probably too much.

Thanks for the advice! (And thanks, re: Daphne's name. That was my daughter's pick.)

mpr2101 said:

Thanks for that! That's good to know about the red lights. (I also think the red looks a bit strange, and I don't have to live under them). I'll replace them. Also good to know about the timing for the lights. Thank you! As long as we're on the topic, I've always wondered: is there a better way to do lights than bulbs directly over their heads? I've always wondered if the direct light is too intense for them.

Heat wise, I'd read that one side of the enclosure should be in the 90 - 100 range, and the other side shouldn't go below 65. I've had a hard time keeping the "hot" side of her enclosure over about 70 with just the CHE. (With all of the lights on, her basking rock registers about 100). Am I overdoing it? She seems to spend a lot of time on her rock, so I assume she likes it. At night, she usually burrows into the substrate under one of her hides, so I figure the soil gets warm in the day, then traps heat at night.

As for UV, we live in Chicago, so there's no going outside for Daphne until May (optimistically) or June (more likely). I have a fluoro tube for UV, which comes on every day; from what you're saying, though, that's probably too much.

Thanks for the advice! (And thanks, re: Daphne's name. That was my daughter's pick.)

Click to expand...

Every enclosure is different. We can tell you the temperature parameters to aim for, but everyone must "custom tune" their heating and lighting strategies and equipment to hit those suggested parameters. It depends on your room temp, climate, season, ventilation, enclosure type, substrate type, dampness, etc... Lots of variables to consider.

You might need multiple basking bulbs to get the right temps for day time, and have those assisted by CHEs. I find it much easier to maintain the correct condition in a large closed chamber that is not open to the cold dry room air.

What type of UV tube have you got? Some are fine to run all day, and some need to be on a timer for a few hours mid day only.

The UV tube is a high output variety ("Reptisun" is the maker, if I'm not mistaken). I'm not sure about its spectral characteristics, though.

As for the 65 watt floods -- those are incandescent? (i.e., not LED, so they throw off heat?)

Thanks for all of the advice! Last question: how do you cover your enclosures? Daphne's indoor pen is something like 6x5; I thought about covering it, but I was worried about using plexiglass near hot lights; and mildly worried about the integrity of large pieces of glass laid over top. Do you do something like a window (like small panes of glass in a frame)?

I'm going to jump in here for the first time in years and years for no particular reason and hopefully answer your most recent question.

With the years I've kept Russians exclusively indoors, and with a lot of offspring produced, I determined (which I think is in line with Tom's experience... hey Tom) that enclosed top is preferable to open. I have some very large, long term captive bred holdback females that are in an open top tub and I don't like it nearly as much as the enclosures I use for the males and other tortoises.

In terms of heat lamps, I use exclusively 38 watt halogen flood bulbs in a wide variety of enclosures. Some of the habitats have higher basking temperatures than others. I used to spend a lot of time trying to dial in everyone's temperatures the same with dimmers, and that was fruitless. I now just make sure the temperatures fall within safe parameters and the tortoises do the rest. In enclosures where the basking temp is on the lower end they spend more time under the heat. In enclosures where it's hotter they just spend less time under it, but strangely enough even in the hottest enclosure the tort still rearranges all of his furnishings, stacks them up and sits on them to get even more heat. He has made some truly astounding basking spots, leaving me scratching my head as to how.

As for a device that can gradually bring the lights on in the morning and off at night, I do have a device that can do that, and works with incandescent or halogen bulbs (no fluorescent). It's a Herpstat 4 by Spyder Robotics (with basking assist), but I have never tried it for that purpose, it's just my thermostat for the snakes. I have a dedicated circuit in the reptile room for heat lamps that's on a hard wired timer, so they get a nice abrupt morning and evening, and that has never produced a problem for me.

P.S. For Russians I wouldn't provide any night time heat unless it regularly goes below 60f.