Design & DIY

Cottage Q&A: Scrubbing bathtub scum

A grimy bathtub By Agenturfotografin/Shutterstock

My cottage bathtub always gets a “matte” finish to it. I think it’s from the water. Or maybe soap scum? It’s really challenging to scrub off, and I’m never sure what to use.—Layla Ivan, via email

Ugh, scrubbing a scummy, stubborn tub! A never-ending task. (Sisyphus feels your misery.)

The water, not the soap, is likely to blame. “It’s usually a function of the hardness of the water and the age of the tub,” says Rob Davis, the owner of EcoEthic in Sunderland, Ont. Groundwater contains lots of minerals, including calcium and magnesium. “And minerals tend to stick more easily to older tubs made of porcelain compared to acrylic tubs,” says Davis.

How do I remove rust from well water?

A septic-safe acid can help break down the scum; one option is food-grade citric acid. “It’s used to clean mineral buildup in coffee makers, toilet bowls, and water softeners,” says Davis. (It’s also a food preservative.) Unfortunately, “currently there is an industry-wide shortage of citric acid. The price has increased by 20 times.” (Because of course there is. And of course it has. Covid is the gift that keeps on taking.)

Your guide to cleaning just about anything at the cottage

Before you fork out a ton of cash or spend hours scouring the internet for citric acid, try a cheap and easier-to-source alternative: vinegar or a non-chlorinated cream cleanser. There’s also EcoEthic’s septic-safe Rust & Mineral Buildup Remover, designed to clean stains from iron deposits and hard water. (Psst: it gets the CL stamp of approval.)

This article was originally published in the March/April 2023 issue of Cottage Life.

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