First Post; LED lighting question

[RabidWombat]

Hi everyone,

TL;DR: Is there a general rule of thumb to calculate the number of LEDs needed for a vivarium based on its size?


I am planning to start a build within the next one to two months for Vietnamese Mossy Frogs. I've got an old 36x16x10 tank that I am going to use. Currently, I'm planning the lighting and will be purchasing this week. This will be my first LED build. I've been tinkering with them for a while for another project, so I'm not entirely new to LEDs. What is new, is using them for plants/animals.

I'm going to go with CREE XM-Ls; cool white and warm white. These seem to have decent coverage in the spectrums that encourage photosynthesis. They also appear to have higher light output than some of the similar LEDs.

My biggest question right now is figuring out how many I need to keep the plants healthy. I've found formulas related to reef tanks but not for vivariums. What is really throwing me off is the info I've seen suggests using a very high number of LEDs, 45-60, on tanks that are not all that much larger than mine. I can see needing more lights when water's involved, but is a similar number necessary for vivariums?

With the dimensions listed above, does anyone have any suggestions? I'll be using 40° optics, approx 4.5" above the top of the viv. Based on this, I can get full light coverage with three sets of lights; 7" from the left and right sides and then one set right in the middle.


Thanks,
RW

[deranged chipmunk]

i'm not exactly sure on the calculations, but you are pretty close with three sets. the numbers for reefs and planted tanks take into account diffusion of light through the water column. par is diffused rather quickly through water, but not through air, so i think you could probably get away with 3 sets, especially since you'll be using the 40 degree optics. that's a nice spread for an LED

[RabidWombat]

Great, thanks! I think it'll work out well. I went ahead and ordered the 3 sets and popped one up with the optic to test the light spread. I think it's going to work out well.

Thanks for taking the time to reply to me. I really appreciate it!

[yuri258]

LED Lighting? Is it proper to discuss this question here in this forum?

[UncleChester]

LED Lighting? Is it proper to discuss this question here in this forum?

Yes this is the right forum for lighting questions, RabidWombat put it in the right place. What is kinda weak imo, is a brand new account popping in attempting to be subtle about the LED lighting they sell with an innocuous question about whether this is the right place to ask about LED lighting. At least make an attempt to add some info here. If you sell LED's and have some experience in their use in terrariums I'm sure everyone would love to tap that know-how.

[DiggenEm]

I dont know how many LEDs you need, but a light guy on the other board told me that its all about the lumens and that 2k lumens per enclosure is optimal. Of course i know this is dependent on enclosure size.