LED's on glass

[alexkharden]

I have 2 reef breeder photon 24's that are going over my 190g DT that will have 23" of water in it. I have two 1/4" pieces of glass that I will be using for a canopy top. I was wondering if there would be any problem lying the led boxes directly on the glass, instead of hanging them above the tank. I'm not worried about air exchange because I have a large sump and oversized skimmer, I know the glass can easily support the weight, and I know that I'll have to keep the intensities lower because the lights will only be 2 1/2 inches off the water if on top of the glass. What I don't know is if the fixtures will overheat or anything, and if having them closer to the water will affect the spread of the light too badly. Can someone give me some guidance? Thanks everyone!

 

[Broadfield]

I have 2 reef breeder photon 24's that are going over my 190g DT that will have 23" of water in it. I have two 1/4" pieces of glass that I will be using for a canopy top. I was wondering if there would be any problem lying the led boxes directly on the glass, instead of hanging them above the tank. I'm not worried about air exchange because I have a large sump and oversized skimmer, I know the glass can easily support the weight, and I know that I'll have to keep the intensities lower because the lights will only be 2 1/2 inches off the water if on top of the glass. What I don't know is if the fixtures will overheat or anything, and if having them closer to the water will affect the spread of the light too badly. Can someone give me some guidance? Thanks everyone!

I have ran LED's on the glass, temporarily until my mounts came in, without any issues at all. I'm not familiar with this fixture, but most have the heatsinks and fans on top... unlike the Radion which has the fan on the bottom. As for spread, you would need to check the angle of the LED's/optics and do the simple geometry to map out where the light spread will be in the tank.

 

[alexkharden]

Ya, these are vented on the sides and back. I actually went ahead and put them up there just to see what I could see, and (to my eye) it looks like there might be a slightly darker section of about 3-4 inches in the center of the tanks. If I had a par sensor I could tell better, but overall it doesn't look too bad really. I guess if I really notice light banding in the tank I could change the standard 90 degree optics for the 120's.

 

[mcarroll]

Instead of not-affording a PAR meter, get a lux meter! Right now!

A free lux meter app on your phone will work, but a $15 handheld is a smart purchase, in my opinion. (e.g. check Galactica Luxmeter on iPhone)

https://www.reefbreeders.com/shop/photon-24/
That appears to suggest you have 90º optics on most or all of your LED's....I think that will give you a problem with spread. (Even pushing it for 120º optics, I think.)

By my calculation, 2.5" of clearance will give each emitter about 5" of coverage at the surface. I think you're going to want at least 10" of space between your tank and the light to get decent front-to-back spread - maybe a full 12". Assuming your tank is 24" from front to back. This is consistent with their FAQ, by the way. https://www.reefbreeders.com/faq/

I also think that airflow around the fixture will be somewhat compromised sitting on the glass vs in open air....but you should ask Reef Breeders their opinion. Their FAQ says on the glass is no problem from a lighting perspective, but they don't address potential heat issues.

 

[Justiful]

Don't do it.

I highly HIGHLY recommend you ditch the glass top idea and go with Clear 1/4in netting instead.

As someone who had actually tried this I can say 100% it frustrates the eyes.
Ignore the fact it will
1. Reduce LED lightspan
2. Cause condensation and salt creep
3. Cause hot spots in tank. (solid spots of light)
4. Decrease par

When those UV and lights strike that glass it travels along the edges and comes out the sides. Along with your other light. Let me show you some pictures.

First picture LED over the acrylic. I took one of my lights off it is in the backround. That is just one of them on half power. That light you see hurts my eyes the way it strikes the edges like that. This is what happens when you place LED's directly on glass or acrylic that is not cut or patterned for diffusion.

Second picture is the light about where it is supposed to be over the water. Some light reflects off, but that is because my light bar is a little big. It does not hurt eyes even at full power with both light bars and is pretty to look at the shimmer effects.

Third picture. My lights with my diffuser. That diffuser fits over the water portion of my tank and basically makes my tank closed. It causes condensation build up and led hot spots off water droplets, in addition to annoying salt creep on top of my tank. Also reflects a lot of the light away. However it doesn't hurt my eyes, the diffuser may look bright but really it is not the ray of death of the first picture.

If you need a cover for your aquarium to prevent fish escaping may I recommend --- http://www.marinedepot.com/Clear_¼_Inch_Netting_with_UV_Stabilizer_for_Aquarium_Screen_Top_Accessories_for_Aquariums-Agriculture_Solutions_LLC-6B1200-FIAQAA-vi.html

If you need to mount those lights on the tank. You can do it by cutting an acrylic mounting bracket and placing them 1-2 inches off water surface. Basicly just make two legs, supporting an acrylic bar.

PS: yes that is cyano. I am working on it. lol.

 

[alexkharden]

Don't do it.

I highly HIGHLY recommend you ditch the glass top idea and go with Clear 1/4in netting instead.

As someone who had actually tried this I can say 100% it frustrates the eyes.
Ignore the fact it will
1. Reduce LED lightspan
2. Cause condensation and salt creep
3. Cause hot spots in tank. (solid spots of light)
4. Decrease par

When those UV and lights strike that glass it travels along the edges and comes out the sides. Along with your other light. Let me show you some pictures.

First picture LED over the acrylic. I took one of my lights off it is in the backround. That is just one of them on half power. That light you see hurts my eyes the way it strikes the edges like that. This is what happens when you place LED's directly on glass or acrylic that is not cut or patterned for diffusion.

Second picture is the light about where it is supposed to be over the water. Some light reflects off, but that is because my light bar is a little big. It does not hurt eyes even at full power with both light bars and is pretty to look at the shimmer effects.

Third picture. My lights with my diffuser. That diffuser fits over the water portion of my tank and basically makes my tank closed. It causes condensation build up and led hot spots off water droplets, in addition to annoying salt creep on top of my tank. Also reflects a lot of the light away. However it doesn't hurt my eyes, the diffuser may look bright but really it is not the ray of death of the first picture.

If you need a cover for your aquarium to prevent fish escaping may I recommend --- http://www.marinedepot.com/Clear_¼_Inch_Netting_with_UV_Stabilizer_for_Aquarium_Screen_Top_Accessories_for_Aquariums-Agriculture_Solutions_LLC-6B1200-FIAQAA-vi.html

If you need to mount those lights on the tank. You can do it by cutting an acrylic mounting bracket and placing them 1-2 inches off water surface. Basicly just make two legs, supporting an acrylic bar.

PS: yes that is cyano. I am working on it. lol.

I decided not to put it on the glass. Not because of the light transmitting through the glass (I couldn't really see what you were talking about in your pics), but because in just bumping the lights around I broke one of the panes. I had to cut it, shortening it by about 5 inches. That got me to thinking, what if that had happened with water/fish/coral in there? A worse break could've sent the light into the drink, frying the light and electrocuting all my livestock. No thanks. I'll still have to hang the lights super low to the water, for the reasons previously mentioned, but they will be hanging, not lying. Question, whatever effect you were talking about before, will that still have an impact if the lights are hanging above the glass by an inch or two, instead of lying directly on it?

 

[Justiful]

I decided not to put it on the glass. Not because of the light transmitting through the glass (I couldn't really see what you were talking about in your pics), but because in just bumping the lights around I broke one of the panes. I had to cut it, shortening it by about 5 inches. That got me to thinking, what if that had happened with water/fish/coral in there? A worse break could've sent the light into the drink, frying the light and electrocuting all my livestock. No thanks. I'll still have to hang the lights super low to the water, for the reasons previously mentioned, but they will be hanging, not lying. Question, whatever effect you were talking about before, will that still have an impact if the lights are hanging above the glass by an inch or two, instead of lying directly on it?

Yes, but it is better than on the glass, glass won't get as hot. Thus less salt creep, and Par will actually be a little better. They are still a paint to deal with. But some people use them. Here is a few articles.
http://www.mrsaltwatertank.com/write-up-wednesday-glass-tops-on-saltwater-tanks/
http://www.aquaristsonline.com/blog/aquarium-care/using-cover-glasses-marine-aquarium-2/ (this look has good info, but my norton malicious advertising on the page, don't click anything on the page)
http://www.saltwatersmarts.com/pros-cons-using-marine-aquarium-cover-glass-acrylic-5241/
http://www.ultimatereef.net/forums/archive/index.php/t-346395.html
http://www.atlantareefclub.org/forums/showthread.php?t=66041


There are pro's and con's. Most reefers choose to go without a glass top. Others use modified tops to reduce the cons, like having an acrylic or glass top with holes drilled in it, and using a plastic sheet at night to stop evaporation. Some use the mesh from BRS, some over ther whole tank, others just over holes where mounts are lighting above. Some use them all the time to stop humidty in their homes.

A minority of reefers for sure use glass tops all the time. Those that do tend to remove them during the day and put on at night or when they are out of town to stop evaporation. More common solutions are canopies, or mesh screens over the tops of the tank. OR a hybrid acrylic/glass and mesh combo. Or even not having a cover.

With glass tops as long as you have a good light that won't be affected by Par decrease, and you know the negatives it may play to some types of dosing styles, and you clean it regularly it can be something worth using. For most it causes more problems then it solves, but it really comes down to what you like. If you like the look of a glass top by all means do it, just read a bit about it so you can alter your maintenance to accommodate it.

 

[alexkharden]

Visually it won't make a difference, the tank is in the wall, so you'd only see the covers inside the room. I was mainly doing it to minimize evaporation and stop awol fish.

 

[Bunnee911]

My ato is the best hundred bucks I have ever spent.