A DIY Aquarium chiller

[Damien]

A few months ago, I lost a lot of shrimps due to high temperature (around 32°C).
So I decided to make an aquarium chiller for my nano (20L).

My requirements were :
- Noiseless
- Able to reduce by 5-7°C a 20L aquarium
- Economic electrically
- Part of the canister filtration system (no visual inconvenience)
- Not pricey (under 100$)
- Shrimp compatible (no copper used)

Becarefull : Aluminium is used to "exchange" the heat. It can be toxic if used in pH below 5.3

During my initial research, I found this interesting article :
http://www.shine7.com/aquarium/chiller.htm

I changed the peltier module used, here are the calculation :


For a 400W Peltier, if I have 4.9V in input, and the local temperature is 32°C, the temperature of my 20L aquarium should be 24°C for 40W used.

Here are all the needed parts :
- Peltier module : TEC1-12726 (50x50mm 400W) around 20$US

- Aluminium Water cooling block (76x68x8mm)
I prefer this one over the classic 50mm one because it's bigger so better thermal exchange

- 12V 240W Power supply (transform AC to DC)

- 100W LED driver (0.8-28V output) (adjust the tension on the peltier module)

- 2 Fan speed controllers (3A DC-DC step down converter)

- 12V Thermostat (the chiller is working only when it needs to)


- Heat sink (Noctua NH-D14)
Based on http://www.frostytech.com/articleview.cfm?articleid=2789&page=4 , this heat sink is perfect



- A 50x50mm copper sheet to make the connection between the heat sink and peltier module. The peltier is bigger than the heat sink base, so I thought it's better to have this sheet to reduce the heat of the Peltier

- 6mm silicon pipe (it's the diameter of the water cooling block)

- 6=>12 water pipe coupler


- Thermal paste

- Electrical cable


All the parts together :

The total cost is around 100$US (greatly depends on the heat sink, i bought mine 2nd hand)

The final build :

Just started to make some test, it's working perfectly!
The only drawback is that it reduce the outflow of my canister filter.

If you have any questions :)

Edited November 2, 2016 by Damien
Minor corrections

[KeenShrimp]

Wow @Damien, that is awesome! Well done. By how much has it reduced your filter flow? 

[jayc]

Wow, very  cool diy.

 

[perplex]

i thought Aluminium is no good for shrimp

[jayc]

Yeah, Alu is not good in tanks with low pH. But better than copper.

 

[perplex]

3 hours ago, jayc said:

Yeah, Alu is not good in tanks with low pH. But better than copper.

 

why low pH? what does it do?

[Damien]

11 hours ago, KeenShrimp said:

Wow @Damien, that is awesome! Well done. By how much has it reduced your filter flow? 

At least by half. I'll try to put the chiller on the input of the canister (it's on the output now). Input and output doesn't have the same diameter, so I'm waiting pipe converters.

 

10 minutes ago, perplex said:

why low pH? what does it do?

Based on that study : http://www.seachem.com/downloads/articles/Aluminum-Solubility-Toxicity.pdf
It's OK to use Aluminium with pH higher than 5.3.
But I'm not chemist, I may misunderstood.

Edited July 10, 2016 by Damien
Corrections

[perplex]

rofl i dont understand that, but wish i knew it was ok above 5.3

 

anyway nice job

[KeenShrimp]

Any pH that is acidic will leach metal ions in a system over time. If your pH is under 7, you are going to end up with Aluminium in the water over time due to corrosion. How much is toxic to shrimp long term?- no-one really knows. Can you reduce Aluminium ion levels with water changes?- absolutely. Will it be enough to prevent potential harm to shrimp?- who knows. As a whole, we as shrimp keepers have many plasticisers leeching into our shrimp eco systems from suction cups, filters, feed bowls, ornaments, tubing etc, and nobody knows what effect that has on fertility, lifespan, metabolism etc of our shrimp. Is aluminium worse than plasticisers? At least you can precipitate the Aluminium with Seachem Prime. Your experience with this will be interesting, please keep us posted on how you go ??

I just want to add that the paper did not include the effect of temperature ( surprising) or that of active biofilms on metals, or if it is an issue at all.  Maybe this is no issue at all for you as long as you don't amp up your CO2. Best of luck with your chiller- it's the coolest DIY one ever. I hope you get the Flow rate fixed as I suspect the pipe adapters might not improve it by much as it will still be constricted through the cooling block- won't it?

[jayc]

Why low pH? See what KeenShrimp said.

Low pH is acidic. The lower the pH the faster the corrosion.

 

 

Damien,

why don't you get a small, slow internal filter/pump for the chiller?

That way you can remove the unit during cooler seasons.
The slower pump will allow better heat exchange.

The slower pump will come with smaller diameter hoses to fit your chiller input.

Something like this...

https://www.bigw.com.au/product/vitapet-crystal-clear-aquarium-filter-200/p/WCC100000000254731/

The outlet of that pump feeds into the inlet of the chiller.

[Rebel]

Superb build indeed. I thought about one of these at a basic level but gave up when I couldn't find stainless steel heat exchange block for the reasons given above.

For the flow issues, the only way is to either have another small loop on your canister or a small pump.

Please let us know how you go!

 

 

[Damien]

On 10/07/2016 at 8:52 PM, KeenShrimp said:

Best of luck with your chiller- it's the coolest DIY one ever. I hope you get the Flow rate fixed as I suspect the pipe adapters might not improve it by much as it will still be constricted through the cooling block- won't it?

Yes, you're right. I'm thinking about designing one myself with bigger hydraulic diameter and get it 3D print.

On 10/07/2016 at 9:32 PM, jayc said:

Damien,

why don't you get a small, slow internal filter/pump for the chiller?

That way you can remove the unit during cooler seasons.
The slower pump will allow better heat exchange.

The slower pump will come with smaller diameter hoses to fit your chiller input.

Something like this...

https://www.bigw.com.au/product/vitapet-crystal-clear-aquarium-filter-200/p/WCC100000000254731/

The outlet of that pump feeds into the inlet of the chiller.

Thank you for your idea!
It's because I have a rimless tank, with just 2 lily pipes in the tank. I don't want to add another thing for visual convenience.
But it's still a good solution ;-)

About the heat exchange, in fact, the better the flow, the better the heat exchange. It's like being out in winter in the wind, always seems cooler than no wind.

[Damien]

9 hours ago, Rebel said:

Superb build indeed. I thought about one of these at a basic level but gave up when I couldn't find stainless steel heat exchange block for the reasons given above.

For the flow issues, the only way is to either have another small loop on your canister or a small pump.

Please let us know how you go!

 

 

The problem with stainless steel is that his thermal resistance is 12 time higher than Aluminium.

About the flow issue, are you talking about a Y junction going to chiller?

[jonomo]

Hi. 

I'm trying to make the same thing and I had a couple of questions... 

Why are you using a 100W LED driver? I'm not sure what this part is for? Can you please explain?

Thanks in advance,

J

[jayc]

29 minutes ago, jonomo said:

Why are you using a 100W LED driver?

I'm pretty sure that's the power supply.

[jonomo]

23 minutes ago, jayc said:

I'm pretty sure that's the power supply.

No.. that would be the 12V 240W Power supply.. 

Is the driver to maintain steady electricity flow?

Edited November 2, 2016 by jonomo
added

[jayc]

Sorry, you're right, I was looking at the wrong picture.

[Damien]

4 hours ago, jonomo said:

Hi. 

I'm trying to make the same thing and I had a couple of questions... 

Why are you using a 100W LED driver? I'm not sure what this part is for? Can you please explain?

Thanks in advance,

J

Hey Jonomo,

The 240W power supply transform AC to DC.
The LED driver adjust the tension. I need that to drive the peltier module. As you can see in my first post, the tension have to be around 4.8V on the peltier module.

Hope it helps

[jonomo]

14 hours ago, Damien said:

Hey Jonomo,

The 240W power supply transform AC to DC.
The LED driver adjust the tension. I need that to drive the peltier module. As you can see in my first post, the tension have to be around 4.8V on the peltier module.

Hope it helps

Ok. So this adjusts the voltage from the power supply (which is 12V) to the peltier (which requires 4.8V)?

I think I need more lessons on how to wire this. Haha.

So far I ordered the peltier, power supply, temperature controller, and heat sink. But I didn't know about this LED Driver.

Thanks for the feedback!

Best,

J

http://www.lazada.sg/dcconverter-5a-volt-regulator-dual-display-export-1347154.html?boost=3

https://shopee.sg/5A-75W-Adjustable-Power-Step-down-Charge-Module-LED-Driver-Red-Voltmeter-CaF8-i.9597431.62780590

Are these the same thing?

 

Edited November 3, 2016 by jonomo

[jonomo]

Looks like the output amp is too low... :(

 

[Damien]

Yes, the driver must provide more current (the current depends on your peltier module).
This is the one i have : 

Laptop Car Led Converter 8A 100w DC-DC Buck Step-Down 4.5-30V to 0.8-28V 95%

[jonomo]

Okay.. I think I understand.. I am thinking of getting this:

http://www.ebay.com/itm/10A-DC-Power-Supply-Adjustable-Module-Step-Down-Power-Voltage-Current-With-Case-/201691044423?hash=item2ef5b91a47:g:5w8AAOSwxKtYASDf

Also, one last stupid question.. What are these things? I circled them in red.. As you can tell I know nothing about this stuff... 

 

Edited November 3, 2016 by jonomo

[Damien]

20 hours ago, jonomo said:

Okay.. I think I understand.. I am thinking of getting this:

http://www.ebay.com/itm/10A-DC-Power-Supply-Adjustable-Module-Step-Down-Power-Voltage-Current-With-Case-/201691044423?hash=item2ef5b91a47:g:5w8AAOSwxKtYASDf

Also, one last stupid question.. What are these things? I circled them in red.. As you can tell I know nothing about this stuff... 

 

Those things are step down converter. They convert the 12V to a lower tension. I use them to control the speed of the heat sink fans.

I have some more research. Instead of using a power supply+led driver, you can use a 5V power supply like this one :
http://www.banggood.com/5V-30A-150W-ACDC-Universal-Regulated-Switching-Power-Supply-5V-Transformer-Switch-for-CCTV-PSU-p-1065075.html?rmmds=search
But you'll need a step up to power the thermostat (it needs 12V).

[jonomo]

2 hours ago, Damien said:

Those things are step down converter. They convert the 12V to a lower tension. I use them to control the speed of the heat sink fans.

I have some more research. Instead of using a power supply+led driver, you can use a 5V power supply like this one :
http://www.banggood.com/5V-30A-150W-ACDC-Universal-Regulated-Switching-Power-Supply-5V-Transformer-Switch-for-CCTV-PSU-p-1065075.html?rmmds=search
But you'll need a step up to power the thermostat (it needs 12V).

HI. Thanks for the response. I noticed that there are 5V peltiers and 5v temperature controllers on eBay, but unfortunately, I already ordered all my components in 12V. I guess I'll just have to try and figure it out and hopefully not burn down the house! Cheers!

[jonomo]

I haven't had a chance to hook it up to my filter yet as I got the wrong sized tubes. I'll have to goto the fish store tomorrow. But here's a sneak peek. 

And a vid!