Tap Vs Distilled Water

Tap water can vary in purity and types of impurities throughout countries and districts, so the question of using purified water (for example distilled/deionised/reverse osmosis RO ) is discussed.

In UK, mains tap water is taken for granted as potable quality, the main variable betweens districts is hardness which relates to the type of rock from where groundwater was sourced.

Below right is 120g of lye dissolved in 400ml of tap water from a moderately high hardness UK district. One the left we have the same quantities of lye/water but this time using distilled water. Note the cloudy precipitation in the tap water compare to the crystal clarity of the distilled.

Our Thoughts So Far On UK Tap Water Use In DpTek

1. The precipitate is insoluble in solvent, so probably neither harmful nor undesireable

2. The precipitate is believed to be the result of dissolved hardness-causing chemicals (magnesium and calcium carbonates) reacting with the lye to form hydroxides (which an not soluble in water)

3. Very little effect on the DpTeks, other than mistaking the cloudiness for undissolved lye

4. This test was applicable for UK water in one district and may not apply to other countries/districts. We would welcome further input.

Source 1 https://water.mecc.edu/courses/ENV115/Lesson18_print.htm

Source 2 Reddit comment by u/JazicInSpace on r/DmtGuide

“When carbon dioxide (CO2) disolves into water a portion of it reacts with the water forming carbonic acid (H2CO3). Any water exposed to the air will be slightly acidic for this reason.

Now carbonic acid will react with mineral magnesium (Mg) and calcium (Ca) to form magnesium carbonate (MgCO3) and calcium carbonate (CaCO3) and will release hydrogen gas (H2). Both magnesium and calcium carbonate are soluble in water.

When you add sodium hydroxide (NaOH) to the solution it reacts with the carbonates to form Calcium Hydroxide (Ca(OH)2), Magnesium Hydroxide (Mg(OH)2) and Sodium Carbonate.

Both Magnesium Hydroxide and Calcium Hydroxide are insoluble in water, in fact this is why Calcium Hydroxide is used in dry TEKs.

Overall this should have little to no effect on your extraction beyond slightly reducing the strength of your lye. It is very likely Calcium and Magnesium are already present in the root bark and the amount even in the hardest water is unlikely to reach the levels found in the bark”