DIY chiller

im likeing the stream tank idea trout are the best looking fish in my opinion...i'd like to do that and just make a chiller with an old fridge or something in my basement...id we'll see where the money takes me

im likeing the stream tank idea trout are the best looking fish in my opinion...i'd like to do that and just make a chiller with an old fridge or something in my basement...id we'll see where the money takes me

I've been toying with an idea, mainly to cool my house in the summer w/o the AC, but it may work as a chiller too. Dig a hole 5-6ft deep (below the frost line and 1 for good measure but the deeper the better) and bury an aluminum coil. Run your water through that and it should keep the water pretty cool all summer, especially in your basement.

This an idea that alot of us have been playing around with for a while. I suspect that it will work great. I am just waiting for someone to make it happen, and see what kind of cooling it will provide. Will it work for multiple tanks? Not sure aluminum is the ticket, but it needs to be metal. Copper?

This an idea that alot of us have been playing around with for a while. I suspect that it will work great. I am just waiting for someone to make it happen, and see what kind of cooling it will provide. Will it work for multiple tanks? Not sure aluminum is the ticket, but it needs to be metal. Copper?

Copper would probably be too toxic. For freshwater, a good stainless steel might work. The best is titanium, but that's obviously a very pricey proposition. I've been thinking about trying to attach a titanium coil to a compressor from a window unit air conditioner. Even relatively small air conditioners have much higher btu ratings than dorm refrigerators and could probably handle more than one average size tank.

EDIT: I forgot to mention, don't try the air conditioner thing unless you have a freon license or have access to someone who does as it would require draining the coolant, soldering on a new coil, and refilling.

Copper reacts pretty quickly and isn't all that soluble. I would not hesitate to use copper but might run salt water through it for a while before use. If you think about it.....just about all of your water already runs through copper pipe before it even gets to your tank. Soft copper tube is pretty cheap and easy to work with as well.

Copper reacts pretty quickly and isn't all that soluble. I would not hesitate to use copper but might run salt water through it for a while before use. If you think about it.....just about all of your water already runs through copper pipe before it even gets to your tank. Soft copper tube is pretty cheap and easy to work with as well.

I was just figuring that aluminum was soft enought to work with and stiff enough to take a load. I got soured on copper during my initial veggie oil conversion on my truck. I was using a coil with hot coolant to heat my secondary veggie oil tank and the veggie polymerized all over the coil and fouled the tank, plugged my filters...not fun. I have abunch of aluminum left over. Wasn't considering the effect acidic water may have on the aluminum (or vice versus).

I have always seen the dorm fridge as an immersion chiller like those used in homebrew wort chilling. The design of these is to act on cooling what they are inserted into, however I have been burned by the outflow, which makes me believe that it would be an efficient system for use with aquaria. You could plug the minifridge into a temperature controller to regulate outflow temperature.

Idea:
 cooler.JPG   18.38KB   3 downloads

Chiller:
 hg5006_1090_general.jpg   13.4KB   2 downloads

What do you all think?

Functionally I think that it would work well for a while. However, I'm not sure that a fridge is intended for near continuous duty that a tank of decent size (especially one required for trout) would require. (see AC idea above for alternative) Plus a continuously running fridge would suck some juice over time. That was why I was thinking of a burried cooling coil that used passive heat exchange in the ground. BUT one of those fridges can be found on the cheap and it has been done before. Give it a go!

Copper reacts pretty quickly and isn't all that soluble. I would not hesitate to use copper but might run salt water through it for a while before use. If you think about it.....just about all of your water already runs through copper pipe before it even gets to your tank. Soft copper tube is pretty cheap and easy to work with as well.

Running salt water through it would be one of the worst things to do. Salt water will start to corrode the copper and produce Copper(II) chloride, which is more than soluble enough to bring the Cu²⁺ concentration up to toxic levels. According to the book Environmental Engineering by Salvato, Nemerow, and Agardy, copper is toxic to fish at concentrations as low as 0.25 mg/l and is toxic to inverts and plants at even lower concentrations than this. Copper piping would probably be ok in most freshwater tanks, but I would try it for an extended time with fish I don't care much about first.

Well corrosion is the exact point. Once you create a "skin" on the copper you create a protective film. The idea is to accelerate corrosion and then get rid of the saltwater. This is basically a way of protecting your freshwater tank by "seasoning" the tubing in advance. Any modifications to the tube after it's been "seasoned" will then expose new copper to the corrosive effects of freshwater and potentially introduce copper.

I tried this with metallic sodium tubing once. It didn't work out.

Well corrosion is the exact point. Once you create a "skin" on the copper you create a protective film. The idea is to accelerate corrosion and then get rid of the saltwater. This is basically a way of protecting your freshwater tank by "seasoning" the tubing in advance. Any modifications to the tube after it's been "seasoned" will then expose new copper to the corrosive effects of freshwater and potentially introduce copper.

The copper pipe will already have a stable oxide layer on it simply from being exposed to air. This is the "skin" that you want on the copper as it is very stable and won't come off in plain freshwater. Salt water has a high concentration of Cl^- anions that will strip the oxide layer off and start to form green-colored copper chloride, which is something that you don't want. It would be far better to flush the pipe with fresh water and never let salt come in contact with the pipe. If the water is neutral to alkaline and not too soft copper is very corrosion resistant and should last quite a while.

I have always seen the dorm fridge as an immersion chiller like those used in homebrew wort chilling. The design of these is to act on cooling what they are inserted into, however I have been burned by the outflow, which makes me believe that it would be an efficient system for use with aquaria. You could plug the minifridge into a temperature controller to regulate outflow temperature.

Idea:
 cooler.JPG   18.38KB   3 downloads

Chiller:
 hg5006_1090_general.jpg   13.4KB   2 downloads

What do you all think?

Something that might make it work better,
I had the same sort of idea, but wanted to have one of them contruction water cooler things you see
on the back of the work trucks in the fridge filled with water and the coils inside of that.
If you turn them small fridges down, they will freeze easy.
Not even past the 3 on the dial should start to freeze milk, ect......

I posted a link a while back to a website where a guy tried this and documented the results. They were not very good - I think he was able to lower the temperature by 4 degrees F. Not worth the effort IMO.

Still, it's fun to talk about it.

I've always thought it would be great to get my hands on one of those lobster display tanks they have in grocery stores [at least they have them here in New England]. They look like they hold about 50 gallons and have chillers and filters built in the cabinet below the tank. I did see one in the Want Adds one time. They wanted $600.00 which is actually not bad considering just the chiller alone costs that from aquarium supply catalogs. Still too much for me though.

Lucky for me I can keep tanks pretty cool in my cellar most of the time. I have a 3 or 4 inch brookie in my darter tank at the moment [they're big darters]. With a cellar window open right behind the tank, the water stays damn cold at this time of year. Even in summer it rarely goes much past 70 F as long as I keep a plain old fan blowing on the tank.

I did see one in the Want Adds one time.

Was it a round one or a square one? The round ones would be especially cool

Was it a round one or a square one? The round ones would be especially cool

It was rectangular but with a curved front.
One day I'm gonna get me one. Not for freshwater though. We have some awesome saltwater fish up here that do not range south of Cape Cod. Consquently they never see water temps above the mid 60s F. Even in my cellar I can't keep water that cool in summer. Especially when you factor in filters, powerheads and lights.

Heh,
The idea of DIY chillers has been around for ages, especially around the Marine Aquarium forums. Metal Halide lighting tends to push the tank temperature into the 90's..making chillers a must. If you want something that'll be super inefficient and ineffective, I would push for the pipe in the fridge... There's a reason chillers are complete power hogs and super expensive... If your goal is 5-10 degrees Fahrenheit, go with a few large computer fans above the water's surface and develop and automatic top-off system. Otherwise have some fun with 100% Isopropyl and Dry Ice...
Just my two cents!

thanks for raining on the parade

What I think should be concidered here,
If the amount of water your letting back to the tank....

Say your running that coil system, and your running a 350gph rated pump on
it on an open flow, the coils would be more heated and the water would not have
time to grab the cold off the tubes,
thus I think it would be recomended that the outflow at the nozzle be restricked down
to a slow stream so the water has time to coll off inthe tube as it runs through it.

Or you could look into a scaled down model of an ice hockey arena and how they do that..

To make the person sick who mentioned the lobster tank set up, one sold someplace around these parts I think it was, like year or so ago for like 100 bucks......... lol