Light/Temp/Humidity Evaluation

[orgetorix]

Hello, I am looking for some evaluation on my lighting, heating and humidity setup for my baby CDT indoor enclosure (36"L x 18"W x 12"H).

Thank you for reading this lengthy post.

Right now, my lighting consists of a 24" HO T5 fixture with an Arcadia 12% and 6.5k Daylight bulb about 9" over the substrate. The heating is a Zoo Med 100W CHE suspended over one end. The lights run 12 hours per day and the CHE is on for 14 hours.

I am concerned that the temps may be too high and the humidity a bit too low. I recently installed some remote sensors and have one inside the hide, one at the midpoint of the enclosure and one a the hot side. I just began getting data off of these yesterday and have compiled the data from 7:00am (one hour before lights/heat on) to 3:00pm (the latest I had info for).



For the first thing, is the temp too high? Looks like the high in the coolest part is almost 95 degrees. Should there be a greater temperature grade? I cannot raise my CHE any higher and I do have a dimmer, so if necessary, I can implement that.

For the humidity, the hide is definitely more humid than the rest of the enclosure but what about the values. The substrate is about 3" of coco cuir with a layer of orchid bark on top. I occasionally water the substrate and can also adjust frequency and amount as needed. In the meantime, there is a water dish that is accessed only sometimes (I'd estimate not even daily), and I have added in a bit more soaking time.

The residents seems to be perfectly happy with great activity and appetite. I just would like to avoid a problem down the road if I can easily prevent it now.

 

[Markw84]

A quick response for now as we need to see pictures of the enclosure and how the lights are mounted, if the enclosure is covered, etc.

But for now, yes, your temps are too high.
You need a thermostat on the CHE so it will simply maintain a set temperature for you.
Your T5 HO 12.0 UVB bulb is way too close to your tortoise. I will potentially burn your tortoise's eyes - like sunblindness - that close. Way too strong UVB at that distance.

 

[orgetorix]

Thanks. I will take some photos when I get home.

To be clear, the potential eye damage is due to the intensity of the UVB bulb and not the overall brightness, right? Should I consider a different, lower-powered bulb or try to raise the light fixture? If I should raise, it about how high?

Right now the top is a screen, but I am having some acrylic panels cut to size to cover as needed.

I will also look in to a thermostat.

 

[Tom]

Mark hit all of my points, but for redundancy, I'll phrase it all again in my own words.

You have a great UV and lighting set up there, but it needs to be mounted at the correct height. Probably around 18-20". If possible, I would run the 6.5K bulb for 12-14 hours a day, but set the 12% tube on a timer to come on for 3-4 hours mid day. This will better simulate that natural mid day UV spike that happens outside. You really need a UV meter in order to properly set the height on that excellent HO bulb. Here is the one to get:
https://www.solarmeter.com/model65.html

Next, I would get rid of the CHE and replace it with a 65 watt flood. Adjust the height of the bulb to get the correct temperature under it, or run it through your dimmer. You really don't need ambient temp maintenance (CHE) and your babies will benefit from a drop to room temp at night. I use CHEs set on thermostats with my tropical species that need warmer night temps.

Many people think DTs need hot dry conditions because they are from the desert. What they usually fail to take into account is that DTs live underground in the desert and they avoid the hot day and cold night by staying in their warm and somewhat damp burrows. Many baby DTs die because of this, so I'm thrilled to see that you already understand this concept. Along these lines, babies should be soaked daily. If they don't need the water daily, it will do no harm. If they did need the water, you just saved their lives.

I house baby DTs exactly the same as baby russians. There lots of tips in here that might help:
http://www.tortoiseforum.org/threads/russian-tortoise-care-sheet.80698/
http://www.tortoiseforum.org/threads/beginner-mistakes.45180/

 

[Markw84]

Thanks. I will take some photos when I get home.

To be clear, the potential eye damage is due to the intensity of the UVB bulb and not the overall brightness, right? Should I consider a different, lower-powered bulb or try to raise the light fixture? If I should raise, it about how high?

Right now the top is a screen, but I am having some acrylic panels cut to size to cover as needed.

I will also look in to a thermostat.

The potential for eye damage is the strength of the UVB. checking actual values in your application using a solarmeter is the only way to know for sure.
I shoot for a UV index (strength of UVB in the bioactive wavelength) of about 3-4 in the primary basking area as a maximum. With a T5 HO 12.0 that is normally about 20" from the light with a reflective hood. I just checked one of mine (T5 HO 12.0 Arcadia) for you, and at 8-9" I get a reading of 13.5! Full sunlight right now, midday in California is 7.4. So yes, that is too close and a UVI that high will cause issues.

 

[Shaif]

Is it detrimental to have the UVB light on longer? Mine is giving nice readings of 3-4 on solarmeter, but I have it on 10 hours. Too much?

 

[Markw84]

Is it detrimental to have the UVB light on longer? Mine is giving nice readings of 3-4 on solarmeter, but I have it on 10 hours. Too much?

You just don't need it on that long. I like to simulate the higher UV at midday so have it on 11am - 3pm. That also will give you 2 1/2 times longer before you need to replace the bulb.

It will not hurt to have it on longer- just unnecessary if you have another light source as your ambient light