UVI at Marty's UVB basking branch

[ajs]

Invested in a solarmeter 6.5R which arrived today and wanted to run the measurements by some of the experienced members here.

lights: 6% Arcadia UVB and 6500K daylight in a double bulb T5HO fixture.
The UVB bulb is 7 months old

His UVB basking branch (~5-6in below fixture):

I know this is well within the effective range of UVI, but I am curious about the bulb life. I feel like if the bulb was still good the UVI should be higher than that there, right? I have seen a chart for this, but can't seem to find it atm.

I see him bask on this branch occasionally, but probably not most of the time that he is basking/hanging out.

I know 7 months for a bulb is a decent length, so should I try buying a new one or could this be a placement/fixture issue?

Zoomed out image for reference:

 

[Pickle-cham]

Are they in a shared reflector?

 

[ajs]

Are they in a shared reflector?

I believe so

 

[Pickle-cham]

This along with the mesh will lower the uvi significantly to the charts. And as the bulb ages this will degrade slowly sort of like a half life. Now you have a solar meter though you could experiment with a 12% more safely

 

[ERKleRose]

This why Solarmeters are recommended for everyone! To make sure bulbs are working properly, I take measurements the day I put them in new and replace them once the readings are cut in half. I do that on every bulb to find the actual rate of decline for when to replace. And to find defective bulbs, too. Granted, by the time I got one, both of my chameleons passed before the bulbs expired to half the UVI output (old age for one and health issues from bad genetics from the breeder for the other one), so I can’t help with comparisons to my readings.

 

[ajs]

Thank you for the replies!

Where do you purchase your replacement UVB bulbs? I originally got mine with the fixture from lightyourreptiles but they don't seem to have Arcadia replacement bulbs from what I saw at the moment

 

[ERKleRose]

I just checked Reptile Basics, and they have T5 HO Arcadia 6% UVB bulbs in 2’, 3’, and 4’ lengths all in stock!

 

[Klyde O'Scope]

I agree with Pickle-cham that it's likely the dual fixture. That UVI sounds reasonable for a 6% w/o reflector. The screen material is another variable. That bulb should be good for at least a year ( I have a Reptisun that's 14 months and still as good as day 1 ); testing it once a month or so will give you a better idea how quickly it is (or isn't) slowly degrading.

Bulb availability can run in spurts—feast or famine. Check back in a month and they may be back in stock (or email them and ask when they expect them in again). I like to keep one spare on-hand for each enclosure, just in case.

 

[Beman]

@Pickle-cham is on the money.... In a dual fixture where they share a reflector for both bulbs... Meaning the reflector does not drop down between the bulbs you need to jump up to a 12% because it reduces the UVI further... If the reflector does drop down in between the bulbs you stay with the 6%.


Also do not take readings from the ends of the bulb. The output there is and will always be less. Go farther in towards the center.

 

[ajs]

I moved the fixture to be more centered over his basking spots. The readings for the spots I see him in most are all within 1-3UVI with the new configuration.

Most of the time he is in the spots that are ~1.5 UVI, but I occasionally see him bask on the branch closest to the bulb that has the 3.1 reading

Is this sufficient, or should I try to shoot for a 3.0 UVI in the areas that he is basking in more often as well?

 

[Beman]

I moved the fixture to be more centered over his basking spots. The readings for the spots I see him in most are all within 1-3UVI with the new configuration.

Most of the time he is in the spots that are ~1.5 UVI, but I occasionally see him bask on the branch closest to the bulb that has the 3.1 reading

View attachment 289198View attachment 289199View attachment 289200

Is this sufficient, or should I try to shoot for a 3.0 UVI in the areas that he is basking in more often as well?

1-3 UVI levels are the usable levels they need. He will be fine... Let him move to the higher UVI if he prefers it. My boys move around in and out of the higher areas and this is normal. They self regulate.

 

[Shanar808]

I wish there was solormeter rental available at the mainstream pet stores. It would make for better lives for many chameleons and their keepers. I recently purchased a double pack of t5 tubes one started dimming in a week and died in a month. It would e saved me an argument with the company if I had the meter for testing.
I’ve read that the screen reduces the light by about 35-40% and multibulb fixtures reduce it by 25-75% depending on the number of bulbs and which slot it is in. It’s tricky trying to figure out the levels without that handy tool.

 

[Klyde O'Scope]

I wish there was solormeter rental available at the mainstream pet stores.

Nice thought, but it would be a nightmare for both customers & stores. These are pretty sensitive units, and must be sent back to the factory periodically for re-calibration. Renting them out would be like renting DVDs. One day you open one up and find peanut butter & jelly all over it, or so many fingerprints & scratches that it won't play more than a minute before stalling or skipping.

An alternative is building your own or having a savvy friend put one together for you.

diy uvi meter

 

[Shanar808]

Nice thought, but it would be a nightmare for both customers & stores. These are pretty sensitive units, and must be sent back to the factory periodically for re-calibration. Renting them out would be like renting DVDs. One day you open one up and find peanut butter & jelly all over it, or so many fingerprints & scratches that it won't play more than a minute before stalling or skipping.

An alternative is building your own or having a savvy friend put one together for you.

diy uvi meter

True, I was thinking like how Home Depot rents out tools or let’s you use some at some stores too. Soo... Any Savvy peeps wanna be my friend?