High-volume, dependable in-line aquarium water pump
Can be used in fresh or saltwater
Quiet operation and low heat exchange
'Quarium Series Pumps are specificially designed for external use with fresh or saltwater aquariums. Quieter and more efficient operation. UL-Listed.
Model 5.5 does not include electrical cord.
MDQ recommended for pressure setups (i.e. in-line pressure filters).
MDQX recommended for free flow setups (i.e. direct return, wet/drys).
The Little Giant 'Quarium series pumps are excellent choices for the modern hobbyist. These are Little Giant's newest pumps, quieter versions of their popular Magnetic Drive series pumps.
The 'Quarium series includes models suited for both pressure (MDQ) and free-flow (MDQX) setups. These pumps are magnetically-driven, with no seals to wear or leak. They are powerful, durable, high-quality pumps designed and built in the USA to service your aquarium's needs for a lifetime.
For In-line use only
Freshwater or saltwater
'Quarium Series MDQ models handle back pressure well - recommended for high head heights or for canister filtration systems
'Quarium Series MDQX models are best suited for free-flow setups, where water encounters very little back pressure
5" x 9.1" x 4"
4.9" x 11.4" x 3.9"
5.3" x 11.9" x 4"
5" x 10-1/2" x 5-1/2"
5.3" x 11" x 5-1/2"
Using an in-line pump with a wet/dry filtration system: Water flows via gravity from the aquarium into the wet/dry filter, and then into the filter's sump. From the sump, it flows into the pump via gravity through a bulkhead installed in the side of the sump. The pump sends water back up into the aquarium from the wet/dry filter's sump. When installing pumps with wet/dry filtration, you'll need to drill into the filter's sump to install the bulkhead, then mount the pump level to the bottom of the filter's sump. You need to siphon water into the pump before turning it on.
Using an in-line pump with canister filtration: Water moves via gravity from the aquarium into the pump. The pump pushes the water through the canister filters, and back up into the aquarium (or UV filter, chiller, etc.). You need to siphon water from the aquarium and flood the pump before turning it on.
Never restrict the inlet flow of any water pump. This will quickly cause permanent motor damage.
You can restrict the outlet flow of the water pump with a ball valve in order to achieve the desired flow rate.
Use ball valves before inlet and after outlet to make pump removal easy and spill free.
Anytime a threaded connection is used, be sure to use Teflon tape. When using barb insert connections to flexible tubing, use hose clamps. (Plastic hose clamps are required for underwater use.)
All water pumps benefit from a regular cleaning. Check the manufacturer's instructions as to how often maintenance should be performed on your particular pump.
Basic Cleaning Steps:
Remove the pump from the system.
Remove filter from the front of submerged pumps and remove debris. Rinse with plain fresh water (no soap).
Remove the impeller housing cover to expose the impeller.
Remove the impeller and the magnet. Inspect them for damage and wash with plain fresh tap water (no soap or abrasives).
Wash out the impeller housing with plain fresh tap water (no soap or abrasives).
Reassemble the pump and re-install it in your system.
Other Cleaning Tips:
Some brands of in-line pumps require periodic oiling to lubricate the motor. Always refer to your owner's manual for instructions on this procedure.
If you have lime or mineral buildup on any part of your pump, you can dissolve these with Lime Off, a product especially designed for removing lime, salt residue, and other hard deposits on aquarium equipment. Make sure to rinse thoroughly with fresh clean tap water before reassembling your pump.
When choosing a water pump type and size, there are several factors to include in your decision. Filtration type, desired flow rate, plumbing and head height, and adding additional devices all come into play. This article helps clear the confusion.
Your primary objective is to maintain a healthy thriving aquatic environment for your underwater plants and animals. To achieve this goal, one of the most critical decisions you'll make is choosing the right pump. Compare pumps here.
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