DIY aquarium cooler options

BeachVacationer · 09/11/2016, 09:09 PM

With a big pump and lighting on my 20L, I need to cool this tank. Without any cooling, it runs at 83.5 which is a bit too warm. When it's at 79.5 with a small fan blowing on the tank, my RBTAs are much fuller and extended more. I've done enough experiments to realize 84 is too hot.

I don't like that fan noise and chillers are out of the question since they make way too much noise also.

What I'm thinking of doing is to attach a peltier device directly on the aquarium glass externally and a large heatsink on the hot side of the peltier device. I'd skip a fan too on the heatsink to minimize noise. Any DIY gurus out there think this is not a good idea? One thing that concerns me is how quickly does the peltier device get cold. Could a rapid temperature drop risk cracking the glass on a 20L?

Ron Reefman · 09/12/2016, 04:29 AM

I'd never even heard of a peltier before reading this post. So I did a small search. Now I'm interested to hear what others say. Especially if anybody is using such a device on an aquarium.

jake87 · 09/12/2016, 05:18 AM

I know you said you didn't want fans but I have two of these http://www.ebay.co.uk/itm/181636377661 wired into a fan controller in my canopy and can barely hear them at mid speed. I also like things to be quiet so I understand your gripe

mjstech · 09/12/2016, 07:02 AM

Glass is more of an insulator so if that way external is very inefficient. You will need to run a fan on the heatsink no matter what. I would suggest keeping with just fan blowing over tank. Try to find a good quality ball bearing style computer fan. Larger size is generally less rpm and less high pitch whine. You could also undervolt it to slow further (lower noise).

mcgyvr · 09/12/2016, 08:48 AM

The peltier will NOT work in the way you want..
You could use an iceprobe or duplicate its functionality but on the outside of the glass is NOT going to work.. Most highly overestimate the efficiency of a Peltier cooler..
https://www.amazon.com/IceProbe-Ther.../dp/B001JSVLBO

Why do you have a "big pump" on a 20L (5 Gallon)?
What type of lighting?
Enclosed canopy?
Ambient room temp?

A fan is the easiest solution and you can get some that are barely audible..
Increasing surface agitation may just be enough to increase evaporation thus cool the water some..

BeachVacationer · 09/12/2016, 09:51 PM

The 20L is the std 20 gallon long tank. This my bubble tip nem only tank with no sump, no skimmer, no hob filter. I just have a big mag drive pump in it for circulation and the intake fitted with a prefilter to provide a simple mechanical filter. Top is basically sealed to prevent a lot of evaporation. I have a fluval full spectrum led lights on top. Tank is not tall so I thin this light is ok for my small RBTAs. The ice probe would be difficult for me to install, although i thought about trying to drill a hole in another 20L when I can get one $20 again. In any event, it looks like I can build my previously described cooler for pretty cheap so that's why I was entertaining the idea. Glass being an insulator would be a disadvantage though. Perhaps I should look into a quiet fan. I think Dyson makes a fan with no moving parts. May look into that I guess. Thanks guys for all your input!

mjstech · 09/13/2016, 12:04 AM

Petsmart is having the $1 per gallon sale, 10, 20, 40. It is their 20g long...you can buy in store, or online with free store pickup.
You can remove the top, and keep up on evaporation as needed would be easiest and will help with oxygen levels if you have more surface movement also and buy a better computer fan, 80 or 120mm low rpm, ball bearing.
Or get two power heads that will put off less heat and remove the mag drive. I would suggest two hydor koralia 240gph, they are rated at 3.5W each. I have two in my 29g and do well for flow. Our tanks are the same footprint, but mine is a bit taller.
And the Dyson fans (that you can't see the blades) still have fans in the bases and are very expensive. Even the knock off ones are too.

mcgyvr · 09/13/2016, 05:34 AM

ok.. simple..Replace that mag drive.. Thats your problem..
Replace it with a powerhead and problem solved..

and when you have heat problems evaporation is your friend.. Don't fight it.. sealing off a tank is a bad move.. You need gas/oxygen exchange..

So there are 2 simple things to fix the problem you caused

09/11/2016, 09:09 PM	#1
BeachVacationer Registered Member Join Date: Apr 2013 Location: Naperville, IL Posts: 546	DIY aquarium cooler options With a big pump and lighting on my 20L, I need to cool this tank. Without any cooling, it runs at 83.5 which is a bit too warm. When it's at 79.5 with a small fan blowing on the tank, my RBTAs are much fuller and extended more. I've done enough experiments to realize 84 is too hot. I don't like that fan noise and chillers are out of the question since they make way too much noise also. What I'm thinking of doing is to attach a peltier device directly on the aquarium glass externally and a large heatsink on the hot side of the peltier device. I'd skip a fan too on the heatsink to minimize noise. Any DIY gurus out there think this is not a good idea? One thing that concerns me is how quickly does the peltier device get cold. Could a rapid temperature drop risk cracking the glass on a 20L?

09/12/2016, 04:29 AM	#2
Ron Reefman Registered Member Join Date: Jul 2009 Location: Cape Coral, FL Posts: 10,431	I'd never even heard of a peltier before reading this post. So I did a small search. Now I'm interested to hear what others say. Especially if anybody is using such a device on an aquarium. __________________ The good thing about science is that it's true whether or not you believe in it. (Neil deGrasse Tyson) Visit my build thread http://www.reefcentral.com/forums/showthread.php?t=2593017

09/12/2016, 07:02 AM	#4
mjstech Registered Member Join Date: Jan 2005 Location: Glendale, AZ Posts: 735	Glass is more of an insulator so if that way external is very inefficient. You will need to run a fan on the heatsink no matter what. I would suggest keeping with just fan blowing over tank. Try to find a good quality ball bearing style computer fan. Larger size is generally less rpm and less high pitch whine. You could also undervolt it to slow further (lower noise). __________________ My current 29 Gallon tank build thread. http://www.reefcentral.com/forums/showthread.php?t=2577872 Current Tank Info: 29 Gallon glass - started 5/23/16 Last edited by mjstech; 09/12/2016 at 07:14 AM.

09/12/2016, 08:48 AM	#5
mcgyvr Registered Member Join Date: Sep 2003 Location: North Carolina Posts: 20,050	The peltier will NOT work in the way you want.. You could use an iceprobe or duplicate its functionality but on the outside of the glass is NOT going to work.. Most highly overestimate the efficiency of a Peltier cooler.. https://www.amazon.com/IceProbe-Ther.../dp/B001JSVLBO Why do you have a "big pump" on a 20L (5 Gallon)? What type of lighting? Enclosed canopy? Ambient room temp? A fan is the easiest solution and you can get some that are barely audible.. Increasing surface agitation may just be enough to increase evaporation thus cool the water some.. __________________ Who me?

09/13/2016, 12:04 AM	#7
mjstech Registered Member Join Date: Jan 2005 Location: Glendale, AZ Posts: 735	Petsmart is having the $1 per gallon sale, 10, 20, 40. It is their 20g long...you can buy in store, or online with free store pickup. You can remove the top, and keep up on evaporation as needed would be easiest and will help with oxygen levels if you have more surface movement also and buy a better computer fan, 80 or 120mm low rpm, ball bearing. Or get two power heads that will put off less heat and remove the mag drive. I would suggest two hydor koralia 240gph, they are rated at 3.5W each. I have two in my 29g and do well for flow. Our tanks are the same footprint, but mine is a bit taller. And the Dyson fans (that you can't see the blades) still have fans in the bases and are very expensive. Even the knock off ones are too. __________________ My current 29 Gallon tank build thread. http://www.reefcentral.com/forums/showthread.php?t=2577872 Current Tank Info: 29 Gallon glass - started 5/23/16 Last edited by mjstech; 09/13/2016 at 12:56 AM.

09/12/2016, 05:18 AM	#3
jake87 Registered Member Join Date: Aug 2016 Posts: 17	I know you said you didn't want fans but I have two of these http://www.ebay.co.uk/itm/181636377661 wired into a fan controller in my canopy and can barely hear them at mid speed. I also like things to be quiet so I understand your gripe

09/12/2016, 09:51 PM	#6
BeachVacationer Registered Member Join Date: Apr 2013 Location: Naperville, IL Posts: 546	The 20L is the std 20 gallon long tank. This my bubble tip nem only tank with no sump, no skimmer, no hob filter. I just have a big mag drive pump in it for circulation and the intake fitted with a prefilter to provide a simple mechanical filter. Top is basically sealed to prevent a lot of evaporation. I have a fluval full spectrum led lights on top. Tank is not tall so I thin this light is ok for my small RBTAs. The ice probe would be difficult for me to install, although i thought about trying to drill a hole in another 20L when I can get one $20 again. In any event, it looks like I can build my previously described cooler for pretty cheap so that's why I was entertaining the idea. Glass being an insulator would be a disadvantage though. Perhaps I should look into a quiet fan. I think Dyson makes a fan with no moving parts. May look into that I guess. Thanks guys for all your input!

09/13/2016, 05:34 AM	#8
mcgyvr Registered Member Join Date: Sep 2003 Location: North Carolina Posts: 20,050	ok.. simple..Replace that mag drive.. Thats your problem.. Replace it with a powerhead and problem solved.. and when you have heat problems evaporation is your friend.. Don't fight it.. sealing off a tank is a bad move.. You need gas/oxygen exchange.. So there are 2 simple things to fix the problem you caused __________________ Who me?