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Saltwater / Gyre pumps

REEF FLOW, EXPLAINED

What is a gyre pump
and how does it work?

A gyre pump creates a broad stream of water across your aquarium. That current can travel down the opposite wall and return through the tank, creating a circulating loop.

① Pump pushes water across →② Water turns downward ↓③ Water returns along the bottom ←

A simplified flow pattern. Rockwork, tank shape and pump settings change the actual current.

Why water movement matters

Flow helps move oxygen-rich water and suspended particles around the aquarium and can keep debris from settling in hard-to-reach areas. Surface movement supports gas exchange. Corals rely on suitable water movement to bring food and nutrients and carry away waste, but their needs differ. A pump moves water; it does not replace filtration, water changes or a cycled biological filter.

Gyre versus a traditional powerhead

Crossflow gyres typically spread water over a wider area, while many conventional powerheads create a more concentrated jet. Both can be useful. Neither guarantees zero dead spots: rockwork, pump position and animal placement affect circulation. Some controllers offer pulses, changing speeds or feed modes; check the specific model.

Placement and adjustment

Start near the upper side of the aquarium, submerged according to the manufacturer’s instructions. Aim across the tank with enough surface movement for gas exchange without splashing or drawing air. Start at a low setting, then adjust while watching fish, sand and coral response. Avoid blasting tissue directly, creating sandstorms or making fish struggle to swim. Rearrange or add flow if debris accumulates behind rockwork; some animals also need calmer areas.

Choosing a pump

Compare tank dimensions and glass thickness, adjustable minimum and maximum output, mounting, controller features, maintenance access and livestock needs. Maximum gallons per hour is a rating, not a guarantee of even flow; the strongest pump is not automatically best. Check that a pump can run gently enough for your tank, and follow the manufacturer’s safety and cleaning directions. Unplug equipment before maintenance and use drip loops and appropriate electrical protection.

Gyre pumps to compare

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These are product links supplied for comparison, not hands-on reviews. Confirm current specifications, size, compatibility, price and availability on each listing.

Sources & further reading

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