Broken Macerator Pumps: Could Your Wastewater Be the Problem?

A macerator pump is one of the hardest-working parts of a boat’s toilet system. It chops waste into a slurry so it can be pumped through narrow hoses to the holding tank or overboard. When it fails, it’s usually at the worst possible time, and it’s rarely cheap to fix.

Why macerators fail

Most macerator failures aren’t down to the pump itself. They’re caused by what the pump has to deal with:

Crystallisation builds up on the impeller, blades and housing, making the motor work harder.
Solids and paper wrap around the blades and slow them down.
Restricted hoses downstream increase back pressure, so the pump runs hot and wears out.

Over time this extra workload burns out motors, breaks impellers and blows seals.

Keep the pump clean from the inside

Because ProPower Marine is a biological treatment, it doesn’t just pass through. Its microbes settle in the toilet pickup, macerator housing and pipework, breaking down organic matter and helping manage deposits that causes wear. A cleaner system means less material reaching the macerator and less strain on the pump.

The 20 mL routine

This simple routine takes 30 seconds and is one preventative maintenance step for your macerator:

Mix 20 mL of ProPower Marine into a glass of water.
Pour it into the toilet bowl.
Tap the flush button for only a second, so the mixture sits around the impeller rather than being pumped away.
Leave it there until you’re next on board.

Do this regularly, ideally each time you leave the boat, and the microbes may help manage organic deposits in the macerator and adjoining pipework between trips.

Already having trouble?

If your macerator is already struggling, start the routine straight away and treat the holding tank as well. If the pump has failed, replace it, then use ProPower to stop the same thing happening to the new one.

Shop and learn more: ProPower Marine Tank Treatment · Dosing guides