UVB Lighting

[rullom]

Hi, im getting back into this hobby and cant remember some things wondering if you all can help me out.
I bought the Reptisun 5.0 T8 UVB 36" - what light fixture does this fit ? is it a different fixture for T5 vs T8 ? I see 34" bulbs and 36" bulbs. I find it hard to believe that there are fixtures that are 34" AND 36". .. so what's up with this.?

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[Beman]

So T8 fixtures require T8 bulbs. T5Ho fixtures require T5 bulbs. Bulbs are 2 inches shorter than fixture length so if you are wanting a 36 inch fixture you want the 34 inch bulb.

We typically recommend the T5HO fixtures and the 5.0 or 6% Uvb bulbs for them. Distance to basking depends on fixture type and screen type. With more details we can provide more info here.

 

[rullom]

TY - actually this was a mis purchase on my part I thought it was a T5h0 - on the chameleon husbandry article I think this one still had decent distance although they didnt specifically mention it but analogous to the other flourescent types. Instruction son box says 6-12" distance unless its poor marketing.

 

[Beman]

TY - actually this was a mis purchase on my part I thought it was a T5h0 - on the chameleon husbandry article I think this one still had decent distance although they didnt specifically mention it but analogous to the other flourescent types. Instruction son box says 6-12" distance unless its poor marketing.

So with a single bulb T8 fixture and reflector and a 5.0 or 6% bulb you can only get a distance of about 3 inches. With a 10.0 and a 12% a distance of about 5 inches. Both of these at these distances put them in an approximate 3 uvi level.

T8 is not a bad fixture but not as good as a T5HO because the cham ends up really close to the screen top.

Most of the companies do not account for the screen reducing the UVI level by about 40%.

And with a T5HO single bulb fixture and a 5.0 or 6% bulb you want a distance of 8-9 inches to the branch. With a 10.0 and a 12% a distance of 11-12 inches to the branch is needed. Both of these at these distances with the T5HO give you the same 3 UVI level.

 

[Venutus1]

HO t5 bulbs in general put out 50% more light and UVB vs, the same length in a t8 tube.

But allot of it is also how well the reflector in the fixture works reflecting the light downward where it is needed.


Here is some bulb info:
IMPORTANT BULB SIZING INFORMATION and HELP ORDERING BULBS

What does T5, T8 and T12 mean?

The "T" in lamp nomenclature represents the shape of the lamp-tubular. The number following the "T" usually represents the diameter of the lamp in eighths of an inch (1 inch equals 2.5 centimeters). T5 lamps have a diameter equal to 5 times an eighth of an inch, or 5/8". These lamps are approximately 40% smaller than T8 lamps, which are one inch in diameter, and almost 60% smaller than T12 lamps, which are 1½" in diameter. The picture above shows diagrams of lamp ends of T5, T8, and T12 lamps. The picture also shows that pin base type of T5 lamps is different from that of T8 and T12 lamps. T5 lamps have a miniature bi-pin base while T8 and T12 lamps use a medium bi-pin base.


T5 lamps are slightly shorter than T8 and T12 lamps and therefore cannot be used as replacements for the larger lamps.


Here are the UVB levels off Arcadia t5 bulbs in specifically a pro t5 fixtures & NOT going thru screening.


Drop it by ABOUT 30-33% if going through screening.

Ultra Violet Index​

Height	6% UV-B	12% UV-B	14% UV-B
300mm / 12″	4.50	8.50	10.50
380mm / 15″	3.60	6.50	7.00
500mm / 20″	2.50	3.80	4.60
600mm / 24″	1.20	2.40	3.20

UVI measurements taken at the very centre of the strongest point using a solar meter 6.5.


NOTE by me
these readings taken DIRECTLY UNDER THE Fixture--
the UV drops off significantly if you go "out of range" to either side of the reflector, ie. like 5" - 8" to either side of the fixture.


Cheers.
Todd