LED lighting warming up my tank

Jc0187 · Jul 14, 2017

First off, I'd like to give a huge thanks to this site and forum users. Everyone here has been a great help with my many many questions.

Ok. So I noticed today that my tank is starting to creep up to 81/82 degrees in the day time. I keep my house at 78 degrees round the clock. At night my tank can drop to around 76-78 degrees. This suggests to me that my LED lighting strip is heating up my tank. My LED's are only around 40 watts and sit right on top of the glass canopy. I'm thinking about raising the LED's a few inches off of the glass canopy in order to allow the heat to disperse in other directions other than inside my tank. I'm curious to know at what height will I lose effectiveness of the lighting ? I have a 75 gallon tank, around 21" deep. I know that my lighting is not very powerful to begin with but I don't want to lose too much in order to get my LR growing nice colors.

CodyRVA · Jul 14, 2017

I highly doubt your LEDs are causing the temp to rise, but who knows. If it were me, I would cool your house down some and see if that makes a difference. I keep my house at 74 degrees and my tank is always at 79; so it's naturally plausible for your tank to climb to 82 if you keep your house at 78.

Jc0187 · Jul 14, 2017

CodyRVA said:
I highly doubt your LEDs are causing the temp to rise, but who knows. If it were me, I would cool your house down some and see if that makes a difference. I keep my house at 74 degrees and my tank is always at 79; so it's naturally plausible for your tank to climb to 82 if you keep your house at 78.

When I put my hand underneath the glass, I can feel the warmth coming off, and it's pretty warm. As for keeping my house cooler, I just can't. I live in Phoenix Arizona and today the outside temp is 110 degrees. Next week we are looking close to 118 degrees. It's not possible to get my air down any further than 77 degrees. It just won't go down anymore without fear of my a/c burning out. There's really no other factors that are raising my temps. It's got to be the lighting.

Reef Pets · Jul 14, 2017

Jc0187 said:
When I put my hand underneath the glass, I can feel the warmth coming off, and it's pretty warm. As for keeping my house cooler, I just can't. I live in Phoenix Arizona and today the outside temp is 110 degrees. Next week we are looking close to 118 degrees. It's not possible to get my air down any further than 77 degrees. It just won't go down anymore without fear of my a/c burning out. There's really no other factors that are raising my temps. It's got to be the lighting.

LEDs do put off some heat. I would recommend raising the ligh off of your canopy and have a fan blow on the tank.
You can put the fan on a timer so it comes on and off at the same time your lights do.
It's a cheap and easy fix.

Jc0187 · Jul 14, 2017

Reef Pets said:
LEDs do put off some heat. I would recommend raising the ligh off of your canopy and have a fan blow on the tank.
You can put the fan on a timer so it comes on and off at the same time your lights do.
It's a cheap and easy fix.

Hmmm ok. How far off the canopy do you suggest?

Reef Pets · Jul 14, 2017

Jc0187 said:
Hmmm ok. How far off the canopy do you suggest?

Probably just a couple inches, just enough to get air flow between the light and tank

Michael Cronmiller · Jul 14, 2017

Agreed , raise the lights a bit and run a fan....if ya need a good a/c guy my step brother lives in Mesa....you should be able to get the a/c a bit cooler without killing it

rock_lobster · Jul 14, 2017

Just reverse your light cycle so it's on during the night when your house is cold and off during the daytime or at least peak hours. Or buy a chiller.

Flippers4pups · Jul 14, 2017

Glass top is holding the heat in, not allowing the water to be cooled by the ambient room air temp and also not allowing gas exchange in the tank.

Just my opinion, I would remove the glass top and build a screen top for the tank and by doing so, it will help with the lights heating the water and aid with gas exchange.

I ditched glass tops about a year into the hobby and have never looked back.

Jc0187 · Jul 14, 2017

Reef Pets said:
Probably just a couple inches, just enough to get air flow between the light and tank

Alright. I'll try that. Thanks!

Jc0187 · Jul 14, 2017

Michael Cronmiller said:
Agreed , raise the lights a bit and run a fan....if ya need a good a/c guy my step brother lives in Mesa....you should be able to get the a/c a bit cooler without killing it

Yea I know but, I rent and our lease is up in a few months. I've already brought this up to my landlord. But hey, thanks for the offer.

Jc0187 · Jul 14, 2017

Flippers4pups said:
Glass top is holding the heat in, not allowing the water to be cooled by the ambient room air temp and also not allowing gas exchange in the tank.

Just my opinion, I would remove the glass top and build a screen top for the tank and by doing so, it will help with the lights heating the water and aid with gas exchange.

I ditched glass tops about a year into the hobby and have never looked back.

Have you had noticeable water evaporation? However, I do like the screen option. Maybe I'll look into that.

Flippers4pups · Jul 14, 2017

Jc0187 said:
Have you had noticeable water evaporation? However, I do like the screen option. Maybe I'll look into that.

No, but I've always had a ATO on my tanks, even dating back into the nineties.

Jc0187 · Jul 14, 2017

Flippers4pups said:
No, but I've always had a ATO on my tanks, even dating back into the nineties.

What is a ATO?

roberthu526 · Jul 14, 2017

How high are the lights from the water? What is your room temperature and how many watts are all your pumps?

Flippers4pups · Jul 14, 2017

Jc0187 said:
What is a ATO?

Auto top off. Replenishes fresh water into your system due to evaporation. Keeps salinity stable and you no longer have to top off fresh water manually.

Jc0187 · Jul 14, 2017

roberthu526 said:
How high are the lights from the water? What is your room temperature and how many watts are all your pumps?

The lights are sitting right ontop of the glass canopy, which is maybe something like 2" from the water surface. The powerheads (2) run 800gph but I have no idea how many watts they are. Room temp is 78.

Jc0187 · Jul 14, 2017

Ob

Flippers4pups said:
Auto top off. Replenishes fresh water into your system due to evaporation. Keeps salinity stable and you no longer have to top off fresh water manually.

oh interesting. I'll look into something like that.

CodyRVA · Jul 16, 2017

Flippers4pups said:
Glass top is holding the heat in, not allowing the water to be cooled by the ambient room air temp and also not allowing gas exchange in the tank.

Good call, +1

n2585722 · Jul 16, 2017

I have canopy with built in LED lighting. The lights are about 14 inches from the water. There is no glass top on the tank. There is an acrylic barrier at the LED's. I have no issue with the LED's adding heat to the tank. There are other things including afternoon sunlight that heat up the room. I do keep the house at 75 degrees and the tank has fans that are controlled by the temp of the water that blow across the sump to cool the tank. The room does get hotter in the afternoon than the rest of the house. The tank does not get any higher that 78.1 degrees unless there is an issue with one of the cooling fans.