Many reef aquarists use some sort of overflow in the tank to take water to an external container called a sump. In the sump various tools such as protein skimmers, carbon containers, reactors, etc. filter the water. The water is then returned to the aquarium. This is referred to as an open loop. The volume of water that flows through this loop need only be 3-4 times the volume of the tank (not 10+). This is the filtration flow rate. The rule of thumb that was mentioned earlier refers to the circulation rate in the aquarium. This number takes into account, not only the return from the filter, but circulation from various other pumps as well. I cannot tell you how many times people have come to me and asked how they can quiet there filter down on their 90 gallon tank because they are trying to put 900 gallons/hr through their overflow.
Circulation pumps (wavemakers) on ebay | 3reef Aquarium Forums
Koralia 3G is the new innovative and unique range of circulation and wave pumps, designed especially to work in reef aquariums. Higher performances, lower energy consumption and quick and easy maintenance are the main features of the Koralia 3G series. The new exclusive Hydor design and technology guarantees a smooth start, continuous and powerful water flow, and can be further managed using the three special attachments and Dual Magnet Support System (DMSS).
Has anyone used the Koralia circulation pumps with a discus aquarium
If you are keeping a larger aquarium (over 40 gallons) then you may want to consider using a closed loop system. Basically this is when water is taken out of the aquarium and fed directly into an external pump and then returned to the tank. The return to the aquarium can be through a hole that is drilled into the side of the aquarium or simply over the back with a plastic pipe. Technically, a canister filter is a closed loop, but for these discussions I will be referring to circulation pumps only. Some advantages to this method are:
Aquarium Circulation Pumps - Aquarium Circulation Pumps & More.
Water movement plays a key role in maintaining fish health in freshwater and marine aquariums. Good water movement is also essential for aquatic plants, corals and even live rock! There are many benefits to increasing water movement in your aquarium with circulation pumps and wavemakers.Some aquariums need recirculation pumps, others don't. Some aquarium creatures need more water movement than others. In fact, for some organisms, extra water movement can be the difference between success and failure, while others will struggle in the current. Your tank's population will dictate if a recirculating pump is necessary.