Tap water can curdle paints.
Quinacridone Rust paint has non-granulating pigment. The color is lovely. However, when mixed with water in a color palette, it curdles and clumps. The same happens when you drop the paint into a wash.
You get an intensively noticeable pattern of granulation. If you mix the paint with another non-granulating paint that’s dark valued (such as phthalo), the pattern of granulation intensifies.
This occurs even if you buy the most transparent paint with adorable color.
The internet barely has reports of paint granulating in tap water. Although hard water can cause the granulation pattern, you (painter) can easily come up with ways of mitigating the curdling and clumping.
Quinacridone (Rose) and Neutral Tint Paints
Quinacridone Rose and neutral tint paints have non-granulating pigments. The two paints also curdle and clump when mixed with tap water but to a lower intensity.
Whether you buy a dud tube or three from the same manufacturer at different times, the effect of hard water on the paints is the same. Even with that kind of effect, you’re less likely to find similar reports or experiences shared on the internet.
That alone is enough to make you go nuts.
Most botanical artists recommend that you use distilled water to mix your paints and watercolor paints.
Tap water is usually hard water. It contains high mineral and acidity content, which easily reacts with paints. This is more so true if you live in a region known to have hard water.
What is Hard Water?
What makes water hard?
Hard water contains high amounts of magnesium and calcium, including other minerals. Unlike water from open water bodies such as streams, rivers, and lakes, groundwater drawn from wells tends to be harder.
Hard water causes mineral deposits (limescale) on fixtures and pipes. It also prematurely degrades water heaters in plumbing fixtures such as pipes.
Therefore, homes in areas with wells use water softeners to make hard water soft. Water softeners are designed to replace minerals such as magnesium and calcium dissolved in the water with sodium.
Saltwater is beneficial for your health when taken as drinking water. However, it affects showerheads and dishes, among other uses of water.
Similarly, art studios need water softeners to convert hard water into soft water. Otherwise, you’ll end up doing your painting with saltwater or limewater.
So, the best advisable way to produce high-quality painting is using soft water to mix paints or watercolors.
Soft water has other amazing benefits.
Designed for different uses; however, water softeners ensure that you get the best salt-free water to mix your paints. Soft water also reduces the wastage of soap when washing clothes.
How to Test the Effects of Tap Water on Your Paint Work
Buy a large bottle of distilled water and wet-on-dry and wet-in-wet painted samples done on similar paper. Compare the paintings using distilled water against hard water.
You’ll realize dramatic differences between the two painting samples. However, expect to see some visible texture on some of the paint-outs using distilled brush water.
Mineral buildups in the pans and on the plates (use them as color palettes) and brush have been attributed to the visible textures. What’s more, tap water is used to wash painting items.
Even if you use fresh tube paints because they’re cleaner, you’re bound to get similar results. The paint is still vulnerable to curdling.
The Best Water for Painting – Distilled Water
Use distilled water in your paintwork to maintain water quality and painting. Your paints can look better than you and drink more water than you actually do.
Invest in a high-quality water softener system based on reverse osmosis to make your hard water safe for drinking and use in your art studio.
If your studio is shared with other artists, installing a water softener may become infeasible. In such a case, fill up a bottle with soft water at home and bring it with you to your painting studio.
However, if you only wash your brushes and color palettes with RO or distilled water, you’re still bound to see some effects of hard water.
You can easily get torn about paint and watercolor manufacturers. Although some paint brands are bright and saturated, they can be prone to curdling and clumping when mixed with tap water.
When running the test, check out your mixing charts to help you determine other paints with unexpected texture.
For instance, Quinacridone pigments from other brands may not clump as much as those mentioned above. However, they may also vary in color boldness.
Soft water or distilled water produces paint-outs with smooth textures.
Mix your non-granulating paint with distilled water free from magnesium and calcium to get smooth textures on your paintings.
Soft water (or distilled water) is of top quality to maintain the quality of your paintings.Painting and Water Quality: Does Hard Water Affect the Quality of Watercolor Paints?