Aquarium Chillers are often needed by hobbyists to lower the temperature of their aquarium water. In addition to the hot summer months, high light levels which are essential in a reef aquarium form an excess build up of heat, which can cause severe damage to your system and death of animals. A chiller is very similar to your home refrigerator, either passing the aquarium water through a heat exchange unit, or passing coolant through a heat exchanger in the tank. Cooling your aquarium water can be achieved by one of two different styles of chillers, drop-in and in-line. Drop-in chillers have and arm with cooling coils at the end which is put in the sump and no plumbing is required, while an in-line chiller has internal cooling coils and has to be plumbed in the line with your setup, water is pumped into the chiller, cooled, and then returned back into the sump or tank. Some things to keep in mind when selecting your chiller; an drop-in chiller requires a little more room next to your setup which the in-line chiller can be plumbed into your setup with piping and can be stored in another room, such as a garage, closet, basement, etc. It is very important that you choose the correct chiller rated for the amount of gallons you are going to cool for optimal performance, that being said, you will have a healthy stable environment for your animals         Chiller Controllers