Sandpaper rough feeling to bottom of pool??

Our pool is extremely rough. Plaster pool, 5 years old, BBB method.

Noticed it this year for the first time. When I put a mask on and swim down to the bottom to inspect, it looks like sandpaper - a smooth plaster bottom, but with many pebble like pieces of sand allover.

Doesn't seem to brush off...

any suggestions.

and yes, we are very well balanced...

thanks

Very well balanced.......does that include a hardness test for minerals?
Wrong hardness levels can cause al sorts of issues with plaster pools.

Quote:

---

Originally Posted by matt4x4

Very well balanced.......does that include a hardness test for minerals?
Wrong hardness levels can cause al sorts of issues with plaster pools.

---

Yes, all is well in that area, checked and double checked by 2 companies.

Anyone able to elaborate on my sandpaper pool plaster problems? cause? solution?

I tried brushing, no effect...