Lighting help; wattage for tube light

Hi all,

I've been scouring the internet, searching for information and learning new things as I go. The next step is to buy a tube light for my terrarium, but I can't find any recommendation as far as wattage, and want to make sure I get the right one.

I have a 90cm x 45cm x 45cm tank, with a metal mesh top, which they say is fireproof. (The company is repti-zoo) I started with a 26W UVB coil bulb and a 25W reptile basking light. I noticed the temperatures weren't warm enough so I bought a 50W basking light and a reflector dome for the UVB, I read that coil bulbs are bad and I'm planning to get a tube light but can't find one in a store around me and need to order online. I live in Prague so I'm thinking an Arcadia over repti-sun, I'm looking at https://www.akva-tera.cz/37726-arcadia-zarivka-d3-desert-reptile-lamp-t8-25w-75cm.html but I'm not sure if 25W is enough. The other option on this website is https://www.akva-tera.cz/37731-arcadia-zarivka-d3-desert-reptile-lamp-t5-39w-85cm.html Snowy is a classroom pet so I am only there consistently 8-5 Monday-Friday, and am a little hesistant to use T5 on top in case there is some problem with the heat and the screen top. Also this would cover almost the whole tank, but there's not much choice on this website for different length and wattage combos. I can also order from Amazon Germany, if there is a specific recommendation someone could give.

Sorry if this question is disjointed, I want to give all the information so that I can make the right choice Thank you for your help! By the way Snowy is 3ish months old, has been in the environment for 2.5 weeks.

90cm long tank , I'd go for a tube no longer than 2/3 the length. So the 24W version is what I'd install.

45cm tall tank, I suggest hang a t5 12% UVB tube (NOT A T8 tube , too weak even if it's a 12% UVB) in a reflector hood UNDER the mesh lid NOT ON TOP.
D3+ Desert Reptile Lamp T5 24W 12%UVB. If they don't stock it , other places will.
I suggest rig the basking spot so it's about 30cm from the UNOBSTRUCTED t5 12%UVB tube + reflector hood.

I don't think of UVB tubes in terms of wattage. I think in terms of requirements, and whatever wattage that comes out to is what it is. The questions I ask myself are (in no particular order):

• T8 or T5 (tube diameter in eighths of an inch). T8 are older tech (shorter range, shorter 6 mo. life); T5 are newer tech (longer range, longer 1 yr. life). Personally, I think it's easier to inhibit a bulb that's too strong than to lower a weaker bulb further into the enclosure, but that depends on other factors. YMMV.
• Length of tube (shooting for ⅔ to ¾ of the length of the enclosure). See: Bearded Dragon Lighting: Everything You Need To Know
• Intensity of bulb (e.g. Reptisun 10.0, Arcadia 12%, Arcadia 14%) For a desert dweller like a BD, Arcadia 12% or 14% is desirable (depending on distance to basking area).

If wattage is an issue due to electricity cost, I'd think about insulating that enclosure. ½" rigid foam insulation (white, pink, or blue) works well, and can be painted/decorated as you like. Another option is multiple layers of corrugated board, alternating the direction of flutes. You can insulate the back, sides, and ½ of the top (allowing for dome light & ventilation). Covering the inside of insulation with Outback landscape is an attractive finish.

Thank you both for your answers! I understand that getting the right kind of light is more important than wattage, however I need to choose when ordering and want to make sure that I am buying one that will be exactly strong enough for my dragon. The electricity isn’t the issue.

Thank you for the very specific recommendation! I am convinced about 60-75 cm long. Can someone else confirm the recommendation of T5 24W with reflectors inside the enclosure? I trust you and really appreciate the response, just want confirmation before I buy, there seems to be a lot of conflicting advice out there.

The wattage has nothing to do with it really, it's all length. For instance, the t5 22 inch bulb ONLY comes in 24w. You can't buy the 22 inch bulb in any other wattage. Obviously, the longer the bulb, the more wattage it takes to excite the gases inside the bulb. So when speaking of these bulbs, we use length as opposed to wattage. Higher wattage in these bulbs doesn't = stronger output. So a 22 inch (24w) outputs the exact same strength as the 34inch (39w) version. All to do with length.

And yes, for your size tank, I'd go with the 22in version.

-Brandon

THANK YOU!

I did not realize that about wattage and had no idea how lights work apparently. Driving myself crazy over this little guy.

Ordering the tube now. Thank you again for everyone who helped!