Because of the many sizes and styles of accessories available in the aquarium market, it is important that when you are searching for the right pump that you know the size of your aquarium, the rate at which the water is going to need to flow, the head pressure, and how much money you are willing to spend. The aquarium pump is considered by some to be the most important component of your aquarium system; so when finding the right pump, be sure to look for quality and suitability rather than only price.
The size of your pump is completely determined by the size of your aquarium. A large aquarium holding a lot of water is obviously going to need much more power than a small fish tank. Usually, the desired flow rate of the water is between 3 and 7 times for saltwater aquariums (depending on whether or not they are fish-only) and 2 and 3 times for freshwater aquariums. You also need to consider the head pressure – the distance from the inlet of the pump to the discharge point in the tank. If you are unsure about the head pressure and the calculations needed to determine your desired flow rate, talk to an aquarium expert or a sales associate at your local pet store; they will be able to help you.
Aquarium pumps come in many styles; however, some of the advantages that certain brands spout over others are their high quality of construction, their quiet running sounds, and their flow control. Also many pumps have a dust filter that extends the life of the pump. There are some pumps that are known for being the cheapest on the market, and these appeal to certain users who are dealing with a tight aquarium budget. However, these pumps are also known for being very noisy and needing frequent repairs. Again, talk to an aquarium expert about what pump is right for your aquarium and how you can get the most out of your money.