UV compact bulb that works

Mark_C

Established Member
Shop guy told me that most info on the CF bulbs is based on old experiences and some of the new bulbs worked quite well.

Dubious as per all the fourum reading, but picked up a few to try out, along with a Solarmeter 6.5 (I bought and one I borrowed one as well to ensure calibration and accuracy).

Enter the surprise. The Exoterra Reptile series, in particular the 26w 150.

Mounted in a normal bowl reflector, I had to lift it 3” off the top screen to DECREASE the coverage for a basking branch 8” below screen.

So, at 11" away I’m getting a solid 2.8-3.1 along the basking branch (and within a foot radius of it all directions).

Just figured I’d share. I’m new and am experimenting with stuff to make a great home for a future bud, so maybe I’m missing something?

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That's pretty interesting! But that's just directly under the bulb right?

No, I actually measured out about a foot in all directions and its pretty solid.
The bulb itself is just above the middle of the basking branch 11" up.
The second photo of 3.8 is about a foot to the left of the branch, and the third shot of 2.8 is at the front of the enclosure, about 18" in front of the branch.
 
Sounds about right. a 4ft T5HO is 48 watts. So if you would need two of the compacts to light the same area, which would also need about 50 watt.

The only down side would be if there was a rapid drop off with distance vs a T5HO. Like at 18-22" its less than 1 or something.
 
Wow very surprising... Another reason every cham owner should have a solar meter. Just curious how close were the two solar meters in their readings? Also make sure you continue to monitor the UVB output. It could be possible those CFLs lose output more quickly over Time.
 
Just curious how close were the two solar meters in their readings?
Very similar, within 0.1 to 0.3, but, of course I couldn’t verify the pinpoint positioning as was done by hand, but numbers were close enough to ensure it was reliable.
 
Shop guy told me that most info on the CF bulbs is based on old experiences and some of the new bulbs worked quite well.
Meh.

Just figured I’d share. I’m new and am experimenting with stuff to make a great home for a future bud, so maybe I’m missing something?
Possibly.

I have to wonder why we're hearing this now rather than previously.
Unless something else has changed, AFAIK, CFLs (either corkscrew or U-shaped) are intended to be mounted horizontally for best coverage/results.
Fluorescent UVBs require a 50-100 hour burn-in period, during which they may put out up to twice as much UVI as rated/after burn-in.

Please don't take this the wrong way—I do not doubt your findings—but I would like to hear of/see others reproduce the results.
 
Fluorescent UVBs require a 50-100 hour burn-in period, during which they may put out up to twice as much UVI as rated/after burn-in.

Please don't take this the wrong way
No offense taken. Im all about facts and reproducibility.
I did leave the bulb on yesterday and today for some burn in time.
I’ll rerun the meter on Sunday, around the 100 hour mark, to see what changes occur.
 
Some of those bulbs can push some light. They’re just less efficient and don’t have anywhere near the penetration of the linear bulbs. Don’t forget to consider what level of UVI is at the screen. It’s always safest to not allow very high levels anywhere within the cage. In my opinion, you’re better off sticking with the technology that has advanced reptile keeping over something that can work, but is a less efficient and effective technology.
Is there a reason your choosing this over the linear T5 bulbs?

Here’s some charts showing the profile of the CFL bulbs and also some with the linear T5 bulbs
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Some of those bulbs can push some light. They’re just less efficient and don’t have anywhere near the penetration of the fluorescent bulbs.
I think you meant linear—CFLs are still fluorescent, and some are T5.

Not meaning to be pedantic here (as I am wont to do)—just trying to head off any confusion.
 
I think you meant linear—CFLs are still fluorescent, and some are T5.

Not meaning to be pedantic here (as I am wont to do)—just trying to head off any confusion.
Agreed

Wait, you’re known to do that? Haven’t noticed 😊

Thanks you are absolutely correct, and I fixed it 😉
 
Ok, the Sunday update as promised.
Bulb has burned in for approx 100 hours.
Looks likes its increased a bit.
I’ll type as I do this.

At basking branch at approx 11” down I’m getting 3.4.
(if interested, I'm using the wedge to simulate a juvenile's size, and the temp at middle of the wedge is 82F)...
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At 2’ down under lamp, slightly offset to right to avoid being in canopy, 1.8…

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At far side of enclosure, approx 18” down and 12” offset to the left, just over the plant canopy, 2.0…

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So, basking branch at 11" at 3.0 - 3.2
18' down in 12" cone is 2.0
24" down in canopy (but under the lamp cone with canopy pushed aside) 1.6 -1.8
Below 24" it drops like a rock, but it seems theres adequate coverage of approx 2.0 or better above the canopy.


Is there a reason your choosing this over the linear T5 bulbs?
I have no objections to T5 as I'm in the Reef tank hobby as well and have em all over the place.
Unfortunately, the smallest unit I have is a 36", need a 24" (spillover isn't an option).
Knowing the reef hobby, and being in many groups, means that a 24" T5HO will become available soon enough, probably for a coral trade or a few token bucks.
So, figured I'd use this for a few weeks/months until I can secure T5.

I'm guessing, hoping actually, that with these numbers I should be OK for a few months.
 
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Ok, the Sunday update as promised.
Bulb has burned in for approx 100 hours.
Looks likes its increased a bit.
I’ll type as I do this.

At basking branch at approx 11” down I’m getting 3.4.
(if interested, I'm using the wedge to simulate a juvenile's size, and the temp at middle of the wedge is 82F)...
View attachment 318455

At 2’ down under lamp, slightly offset to right to avoid being in canopy, 1.8…

View attachment 318456

At far side of enclosure, approx 18” down and 12” offset to the left, just over the plant canopy, 2.0…

View attachment 318457

So, basking branch at 11" at 3.0 - 3.2
18' down in 12" cone is 2.0
24" down in canopy (but under the lamp cone with canopy pushed aside) 1.6 -1.8
Below 24" it drops like a rock, but it seems theres adequate coverage of approx 2.0 or better above the canopy.


Is there a reason your choosing this over the linear T5 bulbs?
I have no objections to T5 as I'm in the Reef tank hobby as well and have em all over the place.
Unfortunately, the smallest unit I have is a 36", need a 24" (spillover isn't an option).
Knowing the reef hobby, and being in many groups, means that a 24" T5HO will become available soon enough, probably for a coral trade or a few token bucks.
So, figured I'd use this for a few weeks/months until I can secure T5.

I'm guessing, hoping actually, that with these numbers I should be OK for a few months.
Understood. These can be used for short periods of time if set up properly to provide adequate UVI for UVB synthesis until you find what you’re looking for.
I would be mindful of any screen walking that your Cham may do under the lamp if it is possible for them to get up there, and they always seem to find a way. It’s likely that the levels are extremely high.
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The max UVI at the screen under a 26W CFL has been measured at nearly four times the highest UVI ever recorded on earth. I am certain you do not want your animal to be able to reach these levels. It will definitely be detrimental to their health
 
Interesting data! And yes as doc said juveniles screen walk like crazy. Mine would hang upside down on the top screen and expose his belly to the UVB until he was almost a year old. I have about 4 inches between the top screen and T5 so the highest he can get is around 6 UVI. Did you take any measurements directly under the light just below top screen... Aka what is the highest possible reading in the cage?
 
Uggggg These types of threads make me nervous for the newbies reading them. They go out buy the cham kit and do not understand that what you bought is very different from what they have... 4 months later their cham has crippling MBD.... Or they buy what you buy and their cham is screen climbing and exposed to levels so extremely high it kills it.

I think there is a fine line what you do in the privacy of your home vs what you say "works" in a forum for others to read and miss interpret.
 
Uggggg These types of threads make me nervous for the newbies reading them. They go out buy the cham kit and do not understand that what you bought is very different from what they have... 4 months later their cham has crippling MBD.... Or they buy what you buy and their cham is screen climbing and exposed to levels so extremely high it kills it.

I think there is a fine line what you do in the privacy of your home vs what you say "works" in a forum for others to read and miss interpret.
I do understand what you mean, and I think everyone should be encouraged to use linear T5HO bulbs because when set up properly and replaced regularly (or as needed if you have a solarmeter) they become the cornerstone of preventing MBD (but only nutritional secondary hyperparathyroidism), and still only part of what’s needed to prevent it

Many more people will buy the Cham kit (this isn’t one of those in this case), and it’s also important that we’re able to show them how to set up what they have to keep their Cham healthy while they get proper equipment

And finally, I’m reluctant to completely discourage those that do it differently. I know it can be confusing for new keepers, but I would guess most, if not all of the most successful keepers, are not following all the rules. And if we discourage everything that doesn’t fit the mold, we can’t learn from these people

If the only goal here is to guide new keepers, then I suppose that’s fine. We have very good templates from the chameleon academy that can guide any new keeper. But if we want to advance knowledge, some of this sort of discussion is essential
 
I do understand what you mean, and I think everyone should be encouraged to use linear T5HO bulbs because when set up properly and replaced regularly (or as needed if you have a solarmeter) they become the cornerstone of preventing MBD (but only nutritional secondary hyperparathyroidism), and still only part of what’s needed to prevent it

Many more people will buy the Cham kit (this isn’t one of those in this case), and it’s also important that we’re able to show them how to set up what they have to keep their Cham healthy while they get proper equipment

And finally, I’m reluctant to completely discourage those that do it differently. I know it can be confusing for new keepers, but I would guess most, if not all of the most successful keepers, are not following all the rules. And if we discourage everything that doesn’t fit the mold, we can’t learn from these people

If the only goal here is to guide new keepers, then I suppose that’s fine. We have very good templates from the chameleon academy that can guide any new keeper. But if we want to advance knowledge, some of this sort of discussion is essential
I honestly just do not like the title.....

UV compact bulb that works​


I have been here long enough to see how people do not fully read or even fully understand. Hell it took me months to fully grasp and understand UVB when I was new. Most will not go buy a solarmeter. Most will see the title and go replicate it. That is where I feel we are doing wrong by others not pointing out that this should not be the go to UVB to use. We get 100's of visitors to this site each day that do not create accounts. We get newbies that create accounts and do not post because they are too scared to. So what do they do here? They read. And they try to make stuff fit their situation.

My only reason for staying in this forum over the last few years is to help newbies. I understand your point fully. I just really hate the title of the thread. When in every other thread we are telling them not to use a CFL and to get a T5HO fixture with a 5.0 or 6% bulb. To me it is very miss leading for those that do not understand enough and think they are doing it right because they read a thread about the CFL that "works"
 
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