Dart Den

Full Version: inside the tank LED ?
You're currently viewing a stripped down version of our content. View the full version with proper formatting.
what are opinions on a in-tank LED ? i understand it would have to waterproof. on the front lip of the tank. do you think something like that would work as far as the light.
It could work, but I think it'd have disadvantages, mostly to due with heat.

LEDs put off less heat than other light sources, but they do put off plenty of heat; if you mount them in the viv, that's heat you're liable to have to figure out how to get rid of, particularly if you're keeping animals that don't do well when they get much above 70 - 80oF.

I've played around with waterproof flexible LED strips, and have used them for viv lights, but even these put out a lot of heat. I've got four rows of them over an 18" Exo-Terra cube next to my desk, mounted on a piece of rigid plastic, and propped about a half-inch off the top glass. I just checked the back of that rigid plastic, and the temp is 117oF, in a 74oF room with a ceiling fan running (temp inside the viv an inch from the top is 77oF).

Going with anything much more powerful than these little strip lights (they're SMD5050 emitters, spaced about 1.5" apart) you have to have more substantial cooling, and that usually means a metal that can dissipate heat well (like aluminum); often with fins to provide extra surface area for cooling (a heat sink). If you don't keep the temp of the LED emitters down under about 130oF - 140oF or so, their life span shortens dramatically. That's why if you look at one of the new consumer LED bulbs (or one of the "LightYourReptiles" bulbs) you'll see that fins to radiate the heat are a big part of the design. Even if the heat source in the tank isn't going to be a problem for a given application, if you use a metal heat sink you'd have to consider how well it will work and survive in humid, often stagnant air.

The short answer is you might get away with using a real low-power waterproof LED strip in the tank just for effect, but I don't think you're going to find a solution that puts out enough light to grow plants without having a lot of problems...
What are you trying to accomplish here Walt ? What is the reason for going inside the tank as opposed to the traditional on top ?
Philsuma Wrote:What are you trying to accomplish here Walt ? What is the reason for going inside the tank as opposed to the traditional on top ?

just something i was thinking/daydreaming about. you know "hey i wonder if this would work". also if it did work you wouldn't have to place the light on top of the tank. wouldn't be in your way when you want to get into the tank. more room on top.
Chuck Lawson Wrote:It could work, but I think it'd have disadvantages, mostly to due with heat.

LEDs put off less heat than other light sources, but they do put off plenty of heat; if you mount them in the viv, that's heat you're liable to have to figure out how to get rid of, particularly if you're keeping animals that don't do well when they get much above 70 - 80oF.

I've played around with waterproof flexible LED strips, and have used them for viv lights, but even these put out a lot of heat. I've got four rows of them over an 18" Exo-Terra cube next to my desk, mounted on a piece of rigid plastic, and propped about a half-inch off the top glass. I just checked the back of that rigid plastic, and the temp is 117oF, in a 74oF room with a ceiling fan running (temp inside the viv an inch from the top is 77oF).

Going with anything much more powerful than these little strip lights (they're SMD5050 emitters, spaced about 1.5" apart) you have to have more substantial cooling, and that usually means a metal that can dissipate heat well (like aluminum); often with fins to provide extra surface area for cooling (a heat sink). If you don't keep the temp of the LED emitters down under about 130oF - 140oF or so, their life span shortens dramatically. That's why if you look at one of the new consumer LED bulbs (or one of the "LightYourReptiles" bulbs) you'll see that fins to radiate the heat are a big part of the design. Even if the heat source in the tank isn't going to be a problem for a given application, if you use a metal heat sink you'd have to consider how well it will work and survive in humid, often stagnant air.

The short answer is you might get away with using a real low-power waterproof LED strip in the tank just for effect, but I don't think you're going to find a solution that puts out enough light to grow plants without having a lot of problems...

i didn't think that heat would be a problem. everything i read says that leds are cooler. i never noticed any sort of heat sink on the lights.
Hmmm.... If you're mainly trying to get the lights off the top (but still have a top that passes light), another possibility might be to do a small "reef style" DIY LED build, and use 40 degree optics to raise it several feet off the top. I've got an open-topped reef tank set up this way, with lights 24 inches above the water (and 50 inches or so off the substrate) that works well; you can get in and out of the tank without ever messing with the lights, and it will still grow coral clear down to the sand bed. It also eliminates any heat transfer issues.

Depending on the size of the viv, it wouldn't take a very big (or expensive) light set up to do this -- a handful of 3 watt cool whites and neutral whites would do a good job of growing plants, but you'd end up having to solder it all up yourself.
pa.walt Wrote:i didn't think that heat would be a problem. everything i read says that leds are cooler. i never noticed any sort of heat sink on the lights.

LEDs are cooler than pretty much anything else, but that still doesn't mean cool :-) Enough LEDs to grow plants still put out a fairly substantial amount of heat -- just a lot less than fluorescents.

Here's my little makeshift light using the waterproof flexible LED strips:

[ATTACHMENT NOT FOUND]

[ATTACHMENT NOT FOUND]

This is just enough light to grow plants and moss in an 18" high vivarium (it could use about 50% more); it still gets to around 115 - 120 degrees (F) after it's been running for a few minutes. Sitting 1/2" off the top glass, that's enough to raise the ambient temperature of the vivarium by 3 degrees or so, even being cooled by a ceiling fan. If it was actually inside the vivarium for a few hours, I'd probably have baked frogs.

For comparison, I just checked the temp on a 13 watt "Jungle Dawn" LED unit that's been on for just short of an hour in a compact Exo top on the tank next to the one above, and it's reading 133 degrees at the heat sink.
chuck thanks for the info. i like i said before never knew that the temp would be that high. i guess it is always ventalation no matter what type of light you use. also it would of been maybe 2 strips instead of the 4 you have. but then again i have no idea how much light that would put out. wonder if you made the lights as part of your lid you could cool it a bit better.
What would probably cool it a bit better would be if I'd use a piece of aluminum or something instead of that plastic. I've kicked around the idea of maybe using a piece of 3" aluminum "U" channel as a piece of the top (with the flat side of the "U" down) and the strips mounted underneath.

It would probably transfer a lot of the LED heat out, and aluminum wouldn't have many corrosion issues, but I'm not sure how well the adhesive on the strips would hold up (nor how frog-safe they are), it'd still have the relatively warm surface of the LEDs where the frogs could conceivably get to it, and it'd still block the view from the top as much as just having the lights above the glass would. It seems like the potential issues would outweigh any advantages.
well was at my local pet smart. they had 3 types of led plus "bulbs." aquion was one brand. it goes on top of the tank. they are the ones with extra leds. you get a one light system but can make it into a three light system if i read the box right. the other two were marineland. one goes on top of the tank and the other can go inside of the tank. it is more of a tube than a retangular light. if one has a local pet smart go check it out. see what you think. i am really thinking of trying the inside one. Smile the only problem is don't know what "K" they are. i did look at them sort quickly.
Walt,

Shoot Todd G. a PM and try to talk with him by phone about LED's....he is one of the best / knowledgeable suppliers I have met.

Todd Goode - lightYourReptiles.com - Yarmouth, Maine
http://lightyourreptiles.com/
pa.walt Wrote:well was at my local pet smart. they had 3 types of led plus "bulbs." aquion was one brand. it goes on top of the tank. they are the ones with extra leds. you get a one light system but can make it into a three light system if i read the box right. the other two were marineland. one goes on top of the tank and the other can go inside of the tank. it is more of a tube than a retangular light. if one has a local pet smart go check it out. see what you think. i am really thinking of trying the inside one. Smile the only problem is don't know what "K" they are. i did look at them sort quickly.

If it's a light sold for aquariums, probably the easiest way to find out how it will work for growing plants in a viv is to go to one of the planted aquarium forums (like plantedaquarium.net or aquaticplantcentral.com) and search on the product name -- if freshwater plant people are having good results with the product, then it should have enough intensity and a proper spectrum to work well in a vivarium also.
the ones i looked at where in the reptile area, so i think they were good for plants. i think i might try one of the lights i mentioned.
if i remember i will look at the marineland and aquion sites and try to find it and maybe post a link to the site.