I did get a response from the paint manufacturer. I thought I'd post it for comments.
1.) The amount of product applied, given the approximate square footage of the surface painted, was approximately 3.0 times the recommended wet film thickness for 1 coat
2.) Two coats are recommended
3.) Under normal circumstances we DO NOT recommend that previously painted pools be acid etched
4.) If etching is employed then the surface should be immediately neutralized with a solution of potable water and baking soda followed by pressure washing
5.) Interior pools should be allowed to dry/cure for a minimum of 10-14 days before being filled with water
6.) Since 14 months elapsed before the problem was observed it is most likely not related to the potentially problematic issues noted in 1 - 5
7.) Since the pool is an interior one UV degradation is probably not a contributing factor
8.) The problem at hand is termed “scale”. Scale is often confused with, and reported as “chalking” paint. In most cases the complaint is noted as “swimmers getting white powder on them when they use the pool”.
9.) In almost all cases, reports that the paint has chalked or oxidized are incorrect. The problem is usually one of water chemistry. When the total alkalinity of the pool is allowed to become too low, some of the minerals in the water drop out of solution. The most common mineral formation we see is calcium carbonate [this is what chalk is made of]. This “scale” is a problem that occurs in both painted and non-painted pools, but is far more noticeable on painted pools, The fine dust formed will normally be everywhere in the pool and will have a greasy or oily feel.
11.) Probable causes are failure to maintain a total alkalinity level of 125 – 150 PPM
12.) There are a number of steps that should be taken to alleviate a “scale problem:
13.) Adjust the total alkalinity to a range of 125 – 150 PPM and the calcium hardness to a range of 175 – 225 PPM
14.) Brush the sides of the pool for 4 – 5 days allowing the filter to run
15.) Add a water “clarifier” to the pool water following label directions. This will bind the small particles of powder so they will be removed by the water filter system. Run the filter for 4 – 5 days at 16 – 20 hours per day.
16.) Add a stain and scale control agent to the pool water.
17.) If this does not solve the problem, the pool may require complete water removal and muriatic acid wash.