HOW TO: DIY Aquarium chiller TUTORIAL

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Some hobbyists live in areas where it might get very hot in certain months. Cooling their aquarium water on a constant basis is something they might need to consider.

In this video, I show you how to build a chiller that you can do at home that will not only work well, but look good, be functional and be cost effective.

I wanted to keep this project under $100 and be universal for any aquarium. As with all my videos, I also needed to create a project that many people would actually be able to do. So simplicity is always key.

Smaller chillers start around $500 for a chiller rated for around 50 gallons.
This project will only cost around $100 for the same size tank, and use less power.

More so, this project will serve to inspire you with a simple idea.

After running on an aquarium for 12hrs, it has no problem with dropping the temperature by 3-5C.

I ran this in my house. I used it on a tank that was at room temp of 22C. It dropped the tank temp to 17C within 12hrs.

It might be able to cool even more, however, i ran it for only 12hrs with 200 GPH on a 50 gallon barrel. If you slow the flow more, it will cool faster.


The king of DIY


What do you think?


Written by The king of DIY

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  1. This does not work. I have a 160 gallon tank and used 100 feet of poly hose and routed it through a chest freezer maximum cooling acquired was 1-2 degrees and the chest freezer condenser practically burned up and the freezer would not drop below 45 degrees. I scrapped this set up and retrofitted a dehumidifier dropping the evaporator coil into a cooler full of antifreeze and had the 100 feet of hose coiled around. The 160 gallon tank is now able to chill to 34 degrees with 70 degree room temps.

  2. Quick question, did anyone accidentally puncture thier refrigerant line when they drilled into the side of the mini fridge? I did, and now my mini fridge is trash 🙁 I want to try again, but I'm scared of ruining another mini fridge

  3. Wow… I went to a boating and fishing convention that has a program for classes to hatch and grow trout for 2 months and I thought about doing something like that at home but you need a chiller for them and I have seen how expensive they are. This may actually make it a possibility for me. Thanks for the video.

  4. You could also use an addition coil in your sump for the heat/cold transfer and if it is a closed system, you could use a freezer and have an antifreeze solution in the hose and bucket in the freezer. This would allow a much colder exchange range and may not require as much tubing. This also would prevent an toxins from cheap hoses entering your tank and killing off your expensive fish or corals.

  5. So I've read a bunch of comments and no one has any temperature comparisons…. To be frank, I'm amazed even the video guy hasn't bothered. Disappointing.

  6. Is this for a marine aquarium? If so, then you should remove the metalic (brass, copper, etc.) ends of the hose. Replace them with plastic. You don't want metals in your tank water.




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