Aquarium Chillers by Lev Ingman

A chiller is a device that is used to cool down your tanks water. There are several different brands of chillers and most of them work the same way. If your tank gets to hot because of intense lighting, lots of electrical equipment being used, or because you live in an area that gets really hot then you need to get a chiller. Most corals will start to die if the tank temperature rises above 82 degrees even its for a short period of time. Often people do not notice that the temperature in their tank is very high, and the result is loss of livestock. Fish and corals are also very sensitive to drastic changes in temperature. The more stable the temperature in your tank is the better.

There are several important things that you need to know when buying a chiller. Do not buy an undersized chiller because you only need to cool your tank by a few degrees and you are assuming that it will work. The chiller will have to work overtime to adjust for those few degrees and will end up being on all the time resulting in premature burn out. The marginal cost of moving up to a higher power chiller is not that significant compared to the overall price of the unit itself. Get the proper sized chiller for your tank.

It is very important that the flow that you put through your chiller is within the recommended flow range because if the flow rate is not within the proper range you can damage your chiller. Often time’s people will plumb a chiller directly into a main circulating pump, but this does not allow for proper flow control even if you try using a ball valve for regulation !! This is why we recommend that everyone set up their chiller on its own power head pump so you can control the exact flow. Remember that flow is reduced over distance and through elbows. If you are pluming your chiller as illustrated in the First Option you need to take into consideration the distance that the water must travel up against gravity from the chiller through the return line and back into the tank. For example if you are pluming water from your tank to a ¼ horse Aqua Euro chiller, which is on the floor, and back into your tank you must find out how far the water has to move back up into the tank. Lets say that the chiller is 2 feet away from the top of the tank, then the water must move against gravity three feet (you do not count the intake of the water because it is basically siphoning down into the chiller and does not cause any resistance). The recommended flow for a ¼ horse Aqua Euro chiller is 590-1020 gallons per hour. You must now find a pump that will do 590-1020 gallon per hour through an elbow at 2 feet.  A RIO 3100 does 782 gallons per hour at 2 feet. (you can find this information on the back of the box’s of most pumps) This rate will be reduced a little bit more because of the elbow, but it will still end up being above 590 gallons per hour.

Several brands of chiller have the option of plugging the heater directly into the chiller unit itself. This gives the chiller thermostat control over the heating and the cooling of the tank so that the chiller is not cooling at the same time that the heater is heating. If your chiller does not come with this option then make sure that your heater and your chiller do not have overlapping ranges of activity. For example, if your heater is set to turn on at 77 and turn off at 80, and your chiller is set to turn on at 82 and turn off at 78, then the range at which they are working overlap and they will fight each other in that range. This will lead to wasteful operation by both of the units, which will loose you money in electricity and ware out your equipment for no reason. To avoid this issue set your heater to turn on at 77 and turn off at 79, then set your chiller to turn on at 82 and turn off at 79. This way the ranges do not overlap and there will not be a problem with the heater and the chiller being on at the same time.

Make sure that your chiller gets proper ventilation because if it does not, it can overheat and break. Often times people put a chiller into their cabinet, and this is ok as long as there is plenty of ventilation. Install a large fan and a vent on the side of the cabinet and you should be fine, but make sure there is ventilation. Many people even opt to place the chiller outside of the cabinet even though it is not the most aesthetically pleasing choice.

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  1. Do not buy an undersized Chiller!
  2. Make sure the flow through your Chiller is correct!
  3. Make sure your chiller and heater are not fighting each other!
  4. Have proper ventilation for your chiller!



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