If you’re planning on setting up a new aquarium, one of the most important things to consider is selecting the right size pump. Your pump is an essential component of the overall filtration system and it plays a crucial role in keeping your tank’s ecosystem healthy and balanced.
Choosing the right pump can seem like a daunting task if you’re new to the aquarium hobby but it’s actually pretty simple once you nail down a few basics:
Determine Your Tank Size
The first step in selecting a pump for your saltwater aquarium is to determine the size of your tank which defines how much water you need to circulate. The capacity of your tank determines the flow rate you need to get from your pump. Most aquarists aim for an hourly flow rate of 4-5 times the volume of the tank. For example, a 50-gallon tank would require a pump that pushes 200-250 gallons per hour or “GPH” as you may see in the product specifications. Keeping your water circulating at that rate will allow the rest of your filtration to work effectively.
Select a Pump Type
There are several types of pumps available on the market, each with their own advantages and disadvantages. Some are simple devices and others will include other components like UV sterilizers or temperature regulators. The two most common categories are submersible and external pumps, both of which will occasionally be supplemented by powerheads.
External or “Inline” pumps
External/inline pumps are typically larger than submersible pumps and are designed to be placed outside of the tank, connected via tubing or hard pipe outlets. They’re generally more powerful than submersible pumps, but they’re also more expensive and can be harder to install. An inline pump will radiate heat away from the water so choosing this option can help keep water temperatures consistent. These pumps can be used to move water out of the tank or return water from a sump back into your main tank.
Submersible pumps
Submersible pumps are the most common type of pump and are designed to be placed inside the tank or a sump filter. They’re relatively easy to install and maintain, and they come in a range of sizes and flow rates. If you choose this option, make sure you have enough room for the pump to fit it with a reasonable amount of clearance around it. Submersibles are easier to install than inline pumps and are a great option for newcomers and most of the common tank setups.
Powerheads & Wavemakers
Powerheads are smaller pumps that are designed to provide additional water circulation within the tank. They are similar to wavemakers but run constantly instead of periodically to simulate ocean waves.
Consider Your Filtration Needs
The size of your pump will also depend on your filtration needs. If you already have other filtration components, be sure to read the instructions that came with those items. Most filtration requires a specific type and size pump. If you have a lot of live rock or other filtration media in your tank, you’ll want to install a slightly larger pump to ensure that the water flows through the media properly.
Don’t forget about height! Most pumps are advertised with a graph of how much water they can move depending on the “pump head” which simply means how high they need to push the water against gravity. A pump that offers “up to 250GPH” will actually push a lot less if the path back to your tank is a few feet upward.
Choose a Reliable Brand
When selecting a pump for your saltwater aquarium, it’s important to choose a reliable brand. it may be tempting to order a cheap model off Amazon or Ebay but those items are often poorly made and may fail quickly. Even if you instal check valves, a poorly sealed pump could open you up to a disastrous scenario where your aquarium drains out into your living space. Spend the extra money to protect your beloved aquatic friends and buy a proven pump that won’t let you down!
