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Opinions on Aquarium Chiller

I am thinking of buying an aquarium chiller to create a highland grow area. My plan is to have a 20 gall terrarium with the aquarium chiller cooling the water at the bottom of the tank, and a few fans to blow the cold air around. Any thoughts/ opinions?
 
I think for it to work (at all) the tank would have to be very well insulated, and even then I don't think it will provide you with temperatures you are looking for, which I assume are in the low 60s and high 50s. Considering the high prices of a chiller, I think you are better suited cooling the tank through a thermoelectric means, or possibly recirculating coolant from a small freezer through a hydroponic radiator with a fan blowing across that. Don't let it scare you, it sounds rather simple (I haven't tried either, but people have done both). There are several links online of projects guiding through step by step instructions. In addition, the radiator idea is clean looking and cheaper than a chiller. Thermoelectric air conditioners are rather expensive on the other hand. However, for all options on the table to work at all, you will need to well insulate the tank. Therefore it would be best if you custom built the tank, in my experience.

This is not to say a chiller would be completely ineffective. It depends on the ambient temps. However, I frankly don't think you will have much luck with it.
 
All you need in that sort of rig, is a way for the fans to rest near the top and push the warmer out of the tank, rather than recirculating the air around the tank. It'll come down to differential density: warmer air is less dense, therefore, it will rest on top of the cooler air. So all you'd have to do is push it out.

Alternatively, a chiller will work fine: http://www.terraforums.com/forums/tropical-pitcher-plants-nepenthes-/140690-evaporative-cooling.html

Thanks for the advice. The chiller you linked wouldn't really work because a) humidity in my house is usually pretty high and b) I need to drop temps ideally around 50-60.
 
Ah I see. I missed the highland part. I haven't done that in a while so I forgot about the night thing... The humidity isn't a big issue because of the design of that cooler but that temp range is a bit harsh if you are wanting a HL rig. It's still possible though, just more trouble. Could use you aquarium chiller to further cooler the air cooler. What chiller did you find btw? I have always wanted to play with one but they are all very expensive (to me, over $100 is expensive).

If I were you, and had access to thermoelectric fans... here's what I might try, just for fun if nothing else. Do what you were going to do with the water on the bottom of the tank with the aquarium cooler probe keeping the water a bit below the air temp you are seeking. Use the TE fans at the top to displace the warmer air near the lighting/lid out. Many tanks already have holes near the back you could utilize for this. I managed to hack 26W (100W equivalent) CFLs into my stock tank lids with just a few mods. Idk how cool those chiller probes get, but this by theory may be able to work. Whether you need an antifreeze agent or I have no idea. I don't think those chillers get that cold though.
 
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I am thinking of buying an aquarium chiller to create a highland grow area. My plan is to have a 20 gall terrarium with the aquarium chiller cooling the water at the bottom of the tank, and a few fans to blow the cold air around. Any thoughts/ opinions?

Okay, first observation. 20 gallons is actually a very small space unless you are only growing seedlings. A 20 gallon long might have more floor space but many varieties of neps will grow too tall for it quickly. An in tank chiller will take up needed floor space and a plunge type chiller will require careful attention to the water reservoir you have beneath the plants.

Second observation. As stated already, you will need to have the fans pulling the warm air out, this will mean, most likely, a custom top, I haven't googled beyond a few minutes but could find no such aquarium cover ready made.

If you go ahead with the project I would suggest wrapping at least three sides of the tank with a insulating blanket that has a reflective side. With the reflective side faced inwards it will help boost light levels.

But my first suggestion, provided you haven't bought anything yet, is to start your project with a larger tank.
 
I haven't bought anything yet. I was searching up the parts I planned to buy and I found out that aquarium chillers cost around $300 when I thought they cost around $70, which means that this is not longer an option. Anyone have any ideas on how I can cool a small tank? Keep in mind I am a 15 year old living in an apartment, so the money I can spend and the space I can take up is limited.
 
You might also consider a 'liquid chiller' that is able to cool temperatures near the freezing point of water, and therefore use liquids with a lower freezing point such as a common coolant. Peltier units are able to do this. This would allow for more efficient heat exchange when it is circulated to a radiator with fans.

Just something to consider, I believe they cost about the same as a aquarium chiller. I would consider circulating water to a reservoir 'sump' and back to a radiator with fans, regardless if a coolant or aquarium chiller is used. You will run into problems with stagnant water during the day, and you won't need a bunch of bulky fans inside the growing space.

a link to liquid chillers. will require wiring, but isn't complicated. They have great customer service and will talk you through all of it. Costs a bit less than an aquarium chiller.
Liquid Coolers - TE Tech Products

here's a video of someone using the radiator-aquarium chiller method. I redact my earlier statement of the affectivity of the aquarium chillers, as clearly this guy was able to do it.
New Highland Terrarium Cooling System - YouTube

here's a link of someone's setup using coolant with a lower freezing point than water. You won't need to use the freezer, however, if you use a liquid chiller that is capable of achieving temperatures near 0 degrees celcius.
http://www.terraforums.com/forums/g...33385-introduction-highland-grow-chamber.html

As always, this will only work with a well-insulated tank if you plan on sustaining a cooler atmospheric temperature throughout the tank, and not just chilling plants directly in front of the fans.
 
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Wow thanks for the links, I will take a look at them right now.
 
  • #10
Wow thanks for the links, I will take a look at them right now.

You are very welcome. I love projects like this. Please update us on what you decide to do! Hopefully when you set it up this thread gets stickied.
 
  • #12
I have a small grow chamber, I considered the chiller idea but it ended up being cheaper for me to just get a cheap hang on air conditioner. It keeps my nights at about 58º most of the year, but on those hot hot central califormia nights its does struggle to keep it at about 60º
 
  • #13
I've never had a highland plant, but I've randomly tooled over ideas on how to chill a doghouse in the past. One thing that may or may not work, someone better versed than me would have to comment, would be a version of the redneck air conditioner. The basic principle is that you take a cooler with the built in cup holders and cut two of them out. You put a small, cheap fan blowing into one and you put an appropriately sized 45 degree pvc angle on the other. You turn on the fan and it blows air across the ice you fill it with an out of the 45. You can turn it whichever way you want to blow the cooler air.

It seems like if you were looking for a cheap method to cool a small space, you could do this with a computer fan, some pvc pipe, a thermostat, and a couple of containers from the dollar store. You could have a couple of pipes running from the tank to a dollar store Rubbermaid container. You'd put the Rubbermaid in the freezer to make block of ice and while one is in the system the other would be in the freezer. The thermostat would tell the pc fan to turn on and it would suck air from in the tank, vs warmer outside air, and blow it across the ice, up the other pipe, and back into the tank.

Granted this is all a little sketchy, but it seems like the idea might work. You could use ice cubes, which are cheap, instead of having a large block of ice and it would last longer if the "cooler" was more insulated, but the idea seems sound. I'm interested to hear what anyone else thinks of this. I know it's not ideal, but would it actually work without too much effort?
 
  • #14
I've never had a highland plant, but I've randomly tooled over ideas on how to chill a doghouse in the past. One thing that may or may not work, someone better versed than me would have to comment, would be a version of the redneck air conditioner. The basic principle is that you take a cooler with the built in cup holders and cut two of them out. You put a small, cheap fan blowing into one and you put an appropriately sized 45 degree pvc angle on the other. You turn on the fan and it blows air across the ice you fill it with an out of the 45. You can turn it whichever way you want to blow the cooler air.

It seems like if you were looking for a cheap method to cool a small space, you could do this with a computer fan, some pvc pipe, a thermostat, and a couple of containers from the dollar store. You could have a couple of pipes running from the tank to a dollar store Rubbermaid container. You'd put the Rubbermaid in the freezer to make block of ice and while one is in the system the other would be in the freezer. The thermostat would tell the pc fan to turn on and it would suck air from in the tank, vs warmer outside air, and blow it across the ice, up the other pipe, and back into the tank.

Granted this is all a little sketchy, but it seems like the idea might work. You could use ice cubes, which are cheap, instead of having a large block of ice and it would last longer if the "cooler" was more insulated, but the idea seems sound. I'm interested to hear what anyone else thinks of this. I know it's not ideal, but would it actually work without too much effort?

@Flip_side_the_pint could you link the AC you use?

[MENTION=12136]Dalton[/MENTION] I've seen many youtube vids on cooler like the one you mentioned but the problem is that I would have to constantly be replacing the ice, which is something I can't do very often and that I do not want to do. If my parents refuse to let me buy anything electrical this might be my only option. The idea itself isn't bad, it's just that constant refilling and emptying would be a pain in the butt :p
 
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  • #15
It may last longer than you think. I know people that backpacked with horses and they had coolers on the packhorses. They had one cooler for each day (it was a large group trip) and said as long as you didn't open them, the one designated for the end of the week would still be cold at the end of the week. So insulation is a part of it. Also, you wouldn't be cycling air from inside your house, but inside the tank, so it would already be cooler. Kinda like the cold air recycle setting in the car. It also wouldn't be running non-stop, but only when the temp rose. I think it would last a good while. It also doesn't have to be ice. It would work as cold water for a good while.

If you're worried about changing it out, I don't think it'd be a big thing. If you wanted to get a little fancier you could put a small drain plug of some sort that you could just pull out when you wanted to drain and put a mop bucket under it. It could be a simple as using a piece of aquarium hose as a siphon and suck-starting it (since the water will be clean) or as complex as drilling a hole, siliconing in a piece of same said aquarium air hose, and putting a small ball valve on it. I figure you can make a system like this very cheaply and fairly maintenance free. The most expensive items would be the pc fan and thermostat.

A bigger cooler would need to be changed less often. You'd gain more time with more insulation. Heck, if you have the room, just set the tank on top of a full sized cooler. It'll have the drain plug and insulation built in. You'll just have to lift the tank off to add more ice or modify it to make it easier.
 
  • #16
If you're planning on investing in a grow tent, you might as well cool the whole room and use an air conditioner. If you do this make sure to get one with a dual-hose function. This will keep the tent around 60 degrees. Keep in mind this option will generate a lot of heat outside the room because of the hot air being pushed out of the air conditioner.

The ice idea will work if you fill it up every night. Otherwise, I would stick with a smaller scale option you were mentioning earlier and perfect that so you don't end up generating more work for yourself.
 
  • #18
Thermoelectric coolers may be cheaper but way less efficient than eg. aquarium chillers. The money you save on aq chiller you loose on TE units as they use so much more electricity - and produce huge amounts of heat. This is of course assuming using an aq chiller that uses compressor and such. Good luck!
 
  • #19
I did this back in college. Now I sort of want to make one again... chiller is still in the basement so...


My advice is to go ahead an buy the biggest one you can afford, because if you skimp and are cheap about it it will be very noisy, run all the time instead of just enough to get your water to desired temp, and will cost you way more in electricity in the long run.

I would suggest you also purchase a separate misting system (They are about 100 but like most things the sky is the limit if you want to get fancy.) Keep the pressure pump for the misting nozzles IN your water under the false bottom. Put a second pump in the reservoir water to feed the chiller in a closed loop. USE TWO THERMOSTATS/TEMP CONTROLLERS because we are dealing with a much smaller volume of water than the chillers were intended for and it could freeze if the stock thermostat malfunctioned. You will want a THIRD therostat/temp controller to hook your misting pump up to.

Just keep the chiller set to 40. Add a small PC fan for air circulation. This little fan alone, moving air across the water (40F) should give you day time temps in the low 70's.
Now add a timer to your misting setup. Once lights go off (Oh yeah, opt for fan-cooled LED fixture) have the mister come on, to be controlled by it's own thermostat (not the chillers) to mist down the tank. In this way you are actually not only cooling the leaves rapidly (and by extension, the media much more slowly) but you are also cooling the sides of the tank and the air it's self. Your mister will come on and off automatically based on the thermostat. You can have your fan turned on 24/7 if you want, or you can get a variable speed fan that can ramp up or down based on temperature.

Insulating the sides and back of your chamber will make it much better. But also much uglier.... Even if you don't insulate the sides and back, I do recommend you put your tank on neoprene foam. Everyone with an aquarium should always do what.

Amazing how quickly things get complicated. By the time you spend $500 on a decent mid-grade chiller, couple hundred on fans, couple to three hundred on lighting, you will really wish you went with something larger than 20 gallons. Ultra highland chambers are a "do it right or don't do it at all" sort of thing. If you don't care about ultrahighland species, you can slack some on the chiller. They really are a "you get what you pay for" item.

I can't really comment on peltier cooling.
 
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  • #20
Thanks for the advice, but I have upgraded! Check out the videos on my instagram: instagram.com/ivanikinz

I decided to get a grow tent instead
 
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