Sometimes pool owners with black or blue plaster notice color fading or changing over time. As pools become more sophisticated design-wise, the color of the surface of the pool becomes more and more creative. Most people aren’t choosing the age-old white plaster surfaces. Some blue or black pools have faded to gray or even white. Needless to say, pool owners are not happy when the color of plaster they chose fades without their permission.
Why does this happen?
Despite contrary belief, studies have shown that it is not the improper balancing of chemicals that changes the pool plaster color. Most of the color changing involves colorfastness in the plaster itself and pool chlorine content. Plaster tinted with the most inorganic dyes were colorfast to bleaching and thus remain the same color over time. Plaster tinted with organic dyes will almost always turn white after exposure to a strong chloride solution. 
Most color manufacturers will warn the applicator they should not use integral color and calcium chloride in the same batch… they don’t mix well.
It is a general consensus that color plaster typically fades either due to chloride admixture incompatibility, bad finishing practices (always read the label!), or the use of organic dies. It could even be a combination of all three of these factors.
How do I prevent it?
To avoid plaster discoloration it is important that you administer the plaster color correctly and follow all manufacturer instructions. Don’t mix chemicals with chlorine that are not compatible and keep in mind that organic dyes are setting you up for color fading or loss.
Another way to prevent plaster color loss altogether is to just stick with the plain white plaster. If you are not yet in the pool construction phase, you may want to consider a vinyl or gunite pool. We suggest considering a vinyl/gunite hybrid for the custom-ability factor.
Have any suggestions on how to keep your color plaster looking sharp? Share with us!
*based on an article first brought to you by AQUA Magazine