When it comes to marine pumps plumbing sanitation, your bilge pump is the last line of defense against water building up in the hull. The decision usually comes down to two priorities: moving a lot of water quickly or keeping a small pump on board that won't drain your battery. Two 12V submersible options at opposite ends of the price scale frame that choice: the SEAFLO 4700 GPH Bilge Pump and the 1100 GPH Submersible Bilge Pump. One is a high-capacity unit with a 2-inch outlet; the other is a compact pump with a 29mm outlet. Comparing them by flow rate, current draw, and construction will tell you which one matches your boat.
Quick verdict: For a larger boat where fast water removal is critical, the SEAFLO 4700 GPH is the more capable pump. For a small boat, a backup pump, or a tight budget, the 1100 GPH model handles routine bilge water at a $90 lower price point.
| Product | Price | Flow Rate | Outlet Diameter |
|---|---|---|---|
| SEAFLO 4700 GPH Bilge Pump | $99.99 | 4700 GPH | 2\" (50 mm) |
| 1100 GPH Submersible Bilge Pump | $9.99 | 1100 GPH | 29 mm (1-1/8\") |
Where each wins
SEAFLO 4700 GPH: If your priority is emergency pumping power, the anti-airlock protection and snap-off strainer base make it a strong choice. The 4-year limited warranty also adds long-term peace of mind.
1100 GPH submersible: For everyday bilge water, the low 8.5A draw is kind to your battery. The stainless steel shaft and thermoplastic body suit wet conditions, and the removable filter makes cleaning simple.
SEAFLO 4700 GPH Bilge Pump (12V, 2\" Outlet)
If the primary job is keeping a larger boat dry, the SEAFLO 4700 GPH is built to move serious water. The 4700 GPH flow rate with a 2-inch outlet means fast evacuation, and the anti-airlock protection helps stop air from stalling the pump. The snap-off strainer base simplifies cleaning, and SEAFLO backs it with a 4-year limited warranty. The trade-off is an appetite for power: it draws 17A continuously (max 32.1A), so it may need heavier wiring and more battery capacity. It's also a heavier unit at 4.4 pounds, so mounting needs to be solid. If you need a dependable primary pump for a medium to large boat, this is the one to reach for.
1100 GPH Submersible Bilge Pump (12V, 29mm Outlet)
For smaller boats and backup duty, the 1100 GPH submersible pump is a practical choice. Its modest 8.5A draw won't strain a small electrical system, and the stainless steel shaft and thermoplastic body are built for wet environments. The removable filter makes cleaning easy, and the pump can run briefly without water, which is handy if your bilge is almost dry. The limitations are also clear: at 1100 GPH with a 29mm outlet, it's not going to keep up with a fast leak on a larger boat. It also comes without any warranty, so it's best treated as a replaceable item. If you just need a small pump to handle rain or splash, this one is a solid pick.
Final choice by use case: Choose the SEAFLO 4700 GPH if you run a medium to large boat and want a primary bilge pump that can clear water quickly in an emergency. Choose the 1100 GPH submersible pump if you're outfitting a small boat, adding a backup, or working within a tight budget and don't need a high-flow unit.
