Been debating this: UV

[Jenblalock003]

Ok it's winter time...so the babies can't go outside just yet. I have them (3 in long) in a 40 gallon tank...75-80 percent humidity temps and substrate perfect but question about UV. Currently have the light (mercury vapor) on for 9-12 hours a day then turn their heat emitter on for night. Is there such thing as too much UV? I soak twice a day and spray them all the time. But just curious....

Ty again!

 

[TortieLuver]

That amount sounds fine....usually you think of uv like sunlight, sun comes up at 7 and sunset 5 or so. You do want to give them a natural setting in the sense of light during day and dark at night.

 

[sibi]

Uvb lighting should be on for at least 10 hours if not more. These bulbs, when used everyday for 12 hours, gives the uvb your tort needs; however, it's nothing compared to what nature can provide (real sun). You can't give too much UVb with these bulbs; you can only have the bulb too close to their carapace causing burns on their shell. Also, keep in mind that these bulbs provides uvb for about six months; thereafter, the light might still work but the uvb is so diminished that it's useless to your tort. You'll need to replace the bulb every 6 months. Again, I stress there is no better source of uvb than the sun. Even in winter, if it's not freezing, your tort can benefit from natural sun if only for 1/2 hour a day. If that's something you can do at least 4 times a week, you won't need the uvb bulb at all.

 

[Jenblalock003]

Uvb lighting should be on for at least 10 hours if not more. These bulbs, when used everyday for 12 hours, gives the uvb your tort needs; however, it's nothing compared to what nature can provide (real sun). You can't give too much UVb with these bulbs; you can only have the bulb too close to their carapace causing burns on their shell. Also, keep in mind that these bulbs provides uvb for about six months; thereafter, the light might still work but the uvb is so diminished that it's useless to your tort. You'll need to replace the bulb every 6 months. Again, I stress there is no better source of uvb than the sun. Even in winter, if it's not freezing, your tort can benefit from natural sun if only for 1/2 hour a day. If that's something you can do at least 4 times a week, you won't need the uvb bulb at all.

Thanks everyone! I feel better. Yea high was 45 F today so no going out. But looking towards 70's this weekend so almost time to go outside. I can't wait.

 

[wellington]

If these are young ones, under a year. I would not put them outside in 70 degree, unless you can block the wind and be sure they are actually getting warmer then 70. This is where a temp gun will help you a lot. Remember, babies being raised the right way, hot and humid, should not be in temps less then 80 with the humidity of 80%. So temps of 70 is too cold for babies unless you can be sure they will get warmer then that and still not over heat.

 

[Jenblalock003]

If these are young ones, under a year. I would not put them outside in 70 degree, unless you can block the wind and be sure they are actually getting warmer then 70. This is where a temp gun will help you a lot. Remember, babies being raised the right way, hot and humid, should not be in temps less then 80 with the humidity of 80%. So temps of 70 is too cold for babies unless you can be sure they will get warmer then that and still not over heat.

That's why I cannot wait until it gets warmer! I know they will love their outside time and here the humidity stays high. So when it's 85/90 outside the humidity will be no less than 80. go away winter!

 

[northernturtleman]

That's why I don't care for Michigan so cold here.

Sent from my LG-LS720 using Tapatalk

 

[compassrose26]

Re: RE: Been debating this: UV

That's why I don't care for Michigan so cold here.

Sent from my LG-LS720 using Tapatalk

I know right? Walking across campus in negative degree weather ain't fun

 

[mikeh]

"You can't give too much UVb with these bulbs; you can only have the bulb too close to their carapace causing burns on their shell."

This is incorrect. There sure is such thing as too much UV. Putting UVB light closer to the tortoise sure does increase UV output and can be dangerous with strong UVB lights at closer then manufacturer recommended distance.

We just had a member measure his UV output of a MegaRay MVB, with readings equivalent of UV index 10 or higher at 14" distance. That is very high UV and can be dangerous if tortoise spends extended period of time under the light.

Either follow manufacturer recommended distance for the species, or better, invest in a UVB meter and set height of the bulb to achieve desired UV index.

 

[Jenblalock003]

"You can't give too much UVb with these bulbs; you can only have the bulb too close to their carapace causing burns on their shell."

This is incorrect. There sure is such thing as too much UV. Putting UVB light closer to the tortoise sure does increase UV output and can be dangerous with strong UVB lights at closer then manufacturer recommended distance.

We just had a member measure his UV output of a MegaRay MVB, with readings equivalent of UV index 10 or higher at 14" distance. That is very high UV and can be dangerous if tortoise spends extended period of time under the light.

Either follow manufacturer recommended distance for the species, or better, invest in a UVB meter and set height of the bulb to achieve desired UV index.

I have 100 watt mercury vapor bulb...the tank is little over 18 inches high. It sits right at 16-17 inch mark. They move around a lot, sometimes under light sometimes not. Temps stay between 85-98...humidity never less than 70 and only gets far low if I'm gone a while. Just want it to be warm outside and ill feel soooo much better.

 

[sibi]

Actually, the information to the op was that the UV bulb can cause burns IF too close. At the recommended heights, there's no chance that the carapace will receive too much uvb rays with these bulbs.For one, these bulbs lose it's strength as the hours and days go by; therefore, I don't believe the bulbs put out as much uvb rays as the even one hour of real sun light. Secondly, torts don't generally sit under the bulb for hours on end. When they feel hot, they move away from the heat. So, really, torts don't get an excess of uvb...just too hot to burn their carapace if they don't have a cool spot to move to.

Let's not nick pick on this issue to demonstrate who is more knowledgeable on topics. It's actually petty to even argue. The only true overdose of UV rays is the natural sun, period.

"You can't give too much UVb with these bulbs; you can only have the bulb too close to their carapace causing burns on their shell."

This is incorrect. There sure is such thing as too much UV. Putting UVB light closer to the tortoise sure does increase UV output and can be dangerous with strong UVB lights at closer then manufacturer recommended distance.

We just had a member measure his UV output of a MegaRay MVB, with readings equivalent of UV index 10 or higher at 14" distance. That is very high UV and can be dangerous if tortoise spends extended period of time under the light.

Either follow manufacturer recommended distance for the species, or better, invest in a UVB meter and set height of the bulb to achieve desired UV index.

 

[Tom]

Jen, the natural range of the sulcata is near the equator, so I like to give them around 12 hours of "sun" a day. You will not "overdose" them on UV with a single MVB at 17".

I sun my guys in a dry black tub when the outside temps are 65 and above and sunny. The tubs block the wind and they get much warmer than ambient temp. Due to the low angle of the sun in winter, they always have shade, but I still check the temps early and often to be sure they are all good. I check the surface temps of the tub in and out of the shade and I also check their carapace temp.

After an hour or so of dry sunning, they come back in for a warm soak and return to their indoor enclosure.

Something else that I have recently been learning with my Solarmeters is that there is little to no UV in the early morning or late afternoon, even if its warm and in direct sun. At least not in January in Southern CA there's not. The day I got my Solarmeters I got home about 4:30 PM and unboxed them. Outside temp was about 78 and the sun was still up. I went outside and put my meter pointing directly at the sun in full sun and got a UV Index of 00.1 and only 007 micro watts per sq. cm on the other meter. This was in full direct sun and it felt very warm on my skin. I was very surprised by this. I took the meters inside and put them under a new 24" 10.0 tube that I'm running and got a UV index of 1.1 at tortoise height, which is weak, but its what I expected. If I held the meter 2" from the bulb the UV output went way up, so I know they are working. I took the meters outside the next morning and was surprised to see very little UV until 9 or 930 in the morning. UV levels steadily climbed until around 1 pm, and then started dropping. This is noteworthy because I often sun my tortoises in the winter in the warmer afternoons. My thinking has always been if the sun is directly hitting the animal, then they are getting some UV. I was aware that UV levels are lower in winter due to the angle of the sun, but I was not aware of just HOW LOW they are in the afternoon. And any sort of cloud cover or haze greatly reduces the UVB coming from the sun too. I never realized just how much is filtered out. Exercise and grazing outisde is still great on a cloudy but warm day, but just know they aren't getting much UV on that day. I wonder how much this will change with summer's much stronger UV rays.

Anyhow, if you can get a little real sunshine just two or three times a week, their UV needs will be met. Your indoor MVB is just a bonus, and it won't hurt anything at the distances you are using it at. So, in your case, too much UV is not a concern, even with real sunshine AND your MVB on all day.

Here is a nother concept that Frances introduced me too. UV gradients. Just like our temperature gradients, because your bulb is over one side and you have hiding areas available, your tortoise can choose its UV level the same way it can choose its temperature by proximity to the bulb. The sun is always out and available for 12 hours a day, but the tortoise will only actually put itself in the sun long enough to warm up and/or get the UV it needs. I think our captive environments should give them the same opportunity, and yours does.

 

[sibi]

Thanks Tom for the info. I could always count on you to give a deeper explanation of the topic 😊

 

[Jenblalock003]

Jen, the natural range of the sulcata is near the equator, so I like to give them around 12 hours of "sun" a day. You will not "overdose" them on UV with a single MVB at 17".

I sun my guys in a dry black tub when the outside temps are 65 and above and sunny. The tubs block the wind and they get much warmer than ambient temp. Due to the low angle of the sun in winter, they always have shade, but I still check the temps early and often to be sure they are all good. I check the surface temps of the tub in and out of the shade and I also check their carapace temp.

After an hour or so of dry sunning, they come back in for a warm soak and return to their indoor enclosure.

Something else that I have recently been learning with my Solarmeters is that there is little to no UV in the early morning or late afternoon, even if its warm and in direct sun. At least not in January in Southern CA there's not. The day I got my Solarmeters I got home about 4:30 PM and unboxed them. Outside temp was about 78 and the sun was still up. I went outside and put my meter pointing directly at the sun in full sun and got a UV Index of 00.1 and only 007 micro watts per sq. cm on the other meter. This was in full direct sun and it felt very warm on my skin. I was very surprised by this. I took the meters inside and put them under a new 24" 10.0 tube that I'm running and got a UV index of 1.1 at tortoise height, which is weak, but its what I expected. If I held the meter 2" from the bulb the UV output went way up, so I know they are working. I took the meters outside the next morning and was surprised to see very little UV until 9 or 930 in the morning. UV levels steadily climbed until around 1 pm, and then started dropping. This is noteworthy because I often sun my tortoises in the winter in the warmer afternoons. My thinking has always been if the sun is directly hitting the animal, then they are getting some UV. I was aware that UV levels are lower in winter due to the angle of the sun, but I was not aware of just HOW LOW they are in the afternoon. And any sort of cloud cover or haze greatly reduces the UVB coming from the sun too. I never realized just how much is filtered out. Exercise and grazing outisde is still great on a cloudy but warm day, but just know they aren't getting much UV on that day. I wonder how much this will change with summer's much stronger UV rays.

Anyhow, if you can get a little real sunshine just two or three times a week, their UV needs will be met. Your indoor MVB is just a bonus, and it won't hurt anything at the distances you are using it at. So, in your case, too much UV is not a concern, even with real sunshine AND your MVB on all day.

Here is a nother concept that Frances introduced me too. UV gradients. Just like our temperature gradients, because your bulb is over one side and you have hiding areas available, your tortoise can choose its UV level the same way it can choose its temperature by proximity to the bulb. The sun is always out and available for 12 hours a day, but the tortoise will only actually put itself in the sun long enough to warm up and/or get the UV it needs. I think our captive environments should give them the same opportunity, and yours does.

Thanks so much Tom. That is very interesting and makes a lot of sense. You will have to keep us up to date once it's summer time to see the difference with the UV. You guys are a big help to me so any info I def take in. Thank you again Tom!

 

[mikeh]

Re: RE: Been debating this: UV

Actually, the information to the op was that the UV bulb can cause burns IF too close. At the recommended heights, there's no chance that the carapace will receive too much uvb rays with these bulbs.For one, these bulbs lose it's strength as the hours and days go by; therefore, I don't believe the bulbs put out as much uvb rays as the even one hour of real sun light. Secondly, torts don't generally sit under the bulb for hours on end. When they feel hot, they move away from the heat. So, really, torts don't get an excess of uvb...just too hot to burn their carapace if they don't have a cool spot to move to.

Let's not nick pick on this issue to demonstrate who is more knowledgeable on topics. It's actually petty to even argue. The only true overdose of UV rays is the natural sun, period.

"You can't give too much UVb with these bulbs; you can only have the bulb too close to their carapace causing burns on their shell."

This is incorrect. There sure is such thing as too much UV. Putting UVB light closer to the tortoise sure does increase UV output and can be dangerous with strong UVB lights at closer then manufacturer recommended distance.

We just had a member measure his UV output of a MegaRay MVB, with readings equivalent of UV index 10 or higher at 14" distance. That is very high UV and can be dangerous if tortoise spends extended period of time under the light.

Either follow manufacturer recommended distance for the species, or better, invest in a UVB meter and set height of the bulb to achieve desired UV index.

This is not about nick picking or who is more knowledgeable on the topic. Its about being responsible and providing correct and safe answers/information to the members.

I have quoted your statement where you bluntly stated that one can't provide to much UV with UVB light. "You can't give too much UVb with these bulbs." This is false and I simply corrected you.

Newer generations of UVB lights that are being used more and more as times goes on are much stronger then in the past, allowing more beneficial UVB for indoor keeping. With this advance it is important to know that at too close of a distance these lights can provide dangerous UV levels. That's why manufacturers of most MVBs, T5HO UVB tubes, etc. provide charts of UV levels for different distances, warn of dangerous levels at too close distances, recommend burn in periods, some will only sell certain UVB lights to Zoos only.

Frances who does extensive research on UVB and vitamin D, in her previous posts on the subject, warned as well of UV levels that could be dangerously high to the animal from strong UVB lights at too close of a distance.

It is irresponsible posting uneducated information on topics where wrong information can cause harm to the animals.

 

[sibi]

That exactly my point, Mikeh. The misinformation you are referring to had nothing to do with my claims because I'm talking about the regular uvb lights that most members here buy for their torts. I'm taking about the suggested heights of these bulbs. I'm NOT talking about a few inches height from the torts carapace which CAN cause damage...I've already said that from the beginning. You are creating this misinformation yourself by refusing to see that what I've stated as "safe" CANNOT give UV overexposure. You are insisting that I've suggested that UV dangers can't be had if the tort sits under a bulb that's not at the right height or the carapace can't be burned if a tort sits under a hot lamp for too long. Don't be ridiculous. That's why I'm saying you are nick picking and just picking on something I have not said. The information I gave to the op is right on and does not pose a threat to the health of his tort PROVIDED she uses the UV light properly. I'm done arguing with you on this topic. Remember Mikeh, there are only opinions here. The op can accept or reject a claim, no matter how much research there is on a subject.

 

[Scm133]

Hi everyone! I need to chime in.
I am actually the member that Mikeh was talking about. My new Mega Ray bulb was reading over 300 uW/cm2 at 14 inches from his basking spot, and the temps were 95-100 degrees. My main concern was eye problems if he stayed under that intense light for warmth.
I have been dealing with UVB lights for quite sometime. I also have a a Solar meter 6.2.
In the past, the Repti-Sun, and Mercury Vapor bulbs were not too much of a concern, as long as they were used at the proper distance. I would get readings in my Bearded Dragon cage around 20-40 uW/cm2, which was no problem. Last year I installed a nice Arcadia D3+T5 12% with reflector, and got 120 uW/cm2 directly below the light. His basking spot was 60 uW/cm2 which was fine. He had the option of moving in and out of the UVB as needed, but the main concern is always the basking spot where they spend the majority of their time.
In the case of my Sulcata, I am using the Mercury bulb as my heat source for his basking spot. I realized that the Mega Ray, until it gets burned in, was way too high, and could definitely effect his eyes.
Hope all of this makes sense. Yes, they can move in and out of the UVB source, but they will be driven to stay on the basking spot longer for the warmth. Monitoring the basking spot is important.

 

[sibi]

I'm glad you chimed in. Ay least you realize that your mega ray bulb is not the standard sunglow mvb or UV bulb that I was making reference to. A standard uvb bulb, when positioned at the recommended height cannot produce an overdose of UV so as to be dangerous. Frankly, I don't know why mikeh made reference to your experience when we were comparing apples to oranges. He should apologize to me for his misunderstanding of my comments. This had not been the first time I've had rude remarks made by him.
And, he never apologizes.

Hi everyone! I need to chime in.
I am actually the member that Mikeh was talking about. My new Mega Ray bulb was reading over 300 uW/cm2 at 14 inches from his basking spot, and the temps were 95-100 degrees. My main concern was eye problems if he stayed under that intense light for warmth.
I have been dealing with UVB lights for quite sometime. I also have a a Solar meter 6.2.
In the past, the Repti-Sun, and Mercury Vapor bulbs were not too much of a concern, as long as they were used at the proper distance. I would get readings in my Bearded Dragon cage around 20-40 uW/cm2, which was no problem. Last year I installed a nice Arcadia D3+T5 12% with reflector, and got 120 uW/cm2 directly below the light. His basking spot was 60 uW/cm2 which was fine. He had the option of moving in and out of the UVB as needed, but the main concern is always the basking spot where they spend the majority of their time.
In the case of my Sulcata, I am using the Mercury bulb as my heat source for his basking spot. I realized that the Mega Ray, until it gets burned in, was way too high, and could definitely effect his eyes.
Hope all of this makes sense. Yes, they can move in and out of the UVB source, but they will be driven to stay on the basking spot longer for the warmth. Monitoring the basking spot is important.