RO water & reducing Copper corrosion

Cheap and easy way of treating RO water to reduce Copper corrosion

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I have been reading more and more about reverse osmosis water and about how it is corrosive, use of re-hardeners and calcite filters etc.. to prevent this and the taste of coffee. I thought it would be worth a small project for the Wiki. This article is relevant to people with "Tanked"/"Pour Over machines", who have an RO unit to avoid scaling their let's recap about RO water.

The perception of increased bitterness is going to be down to less electrolytes dissolved in the water. It pretty much doesn't matter what these are. e.g. Potassium Chloride and Sodium Chloride both taste like salt (there might be a small difference in the degree of saltiness). If you put sugar/milk in your coffee then you won't notice anything, but for pure espresso you might.

The main problem here is going to be acidity, if you can keep the pH of the water around 7.5 then you shouldn't have a problem, also corrosion is related to the Volume/speed of water flow. e.g. a pipe passing 100s of litres per day at a relatively high flow rate, vs 2 litres per day in the espresso machine at a very slow flow rate.

Re-hardeners Calcite Filters
Adding back some of the minerals that have been taken out, to improve taste and reduce the corrosive nature of RO water. This can be by a number of methods: hard water mixing, addition of carbonates etc… Unfortunately this means adding an extra in-line cartridge and more expense.

** That's the background and I thought that some research to see if there was a cheap and easy alternative would be worthwhile. (click here to read rest of article)