Why Caravan Grey Water Tanks Smell and How to Maintain Them

When people think about caravan smells, they think about the toilet. But the grey water tank, which collects water from the shower and sinks, is often the bigger problem. It’s the forgotten tank, and it can produce some of the worst odours in the van.

What's in grey water

Grey water isn’t just soapy water. It contains:

food residue and cooking fat from the kitchen sink
soap, shampoo and body oils from the shower
hair, skin cells and toothpaste
detergent and grease from washing up.

All of that is organic material, and it’s food for odour-producing bacteria.

Why grey water tanks smell so bad

Grey water tanks often sit partly full for days, in warm conditions, with no treatment at all. The water goes stagnant, the bacteria multiply and the tank produces hydrogen sulphide, the rotten egg smell. Many vans also have a grey water outlet or vent near the door or awning, so the smell is right where you’re sitting.

Don't forget the pipes

The pipes between the sinks, shower and tank build up a layer of fat and sludge too. Treating only the tank leaves that untouched.

How to treat your grey water system

ProPower Grey Water Tank Treatment uses beneficial microbes to digest the fats, food residue and soap scum in your tank and pipework, and controls the odour at the source.