A rough pool finish does not identify its own cause. Mineral scale can build material onto the surface. Aggressive water can etch cement away. Exposed-aggregate finishes are intentionally textured. Old plaster can simply wear, pit or lose binder. Before choosing acid, sanding, polishing or resurfacing, determine whether the roughness is material added to the finish or material lost from it.
Four Very Different Kinds of “Rough”
| Condition | What is happening | Why it matters |
|---|---|---|
| Mineral scale | Calcium/mineral material precipitates onto the existing surface. | The finish may be underneath a deposit rather than physically worn away. |
| Chemical etching | Aggressive water dissolves cementitious compounds from the finish. | The roughness is loss of surface material, not a removable layer. |
| Exposed aggregate | Aggregate is intentionally revealed during installation. | Texture is a design characteristic, though excessive or uneven exposure can still be a workmanship concern. |
| Age/deterioration | Binder loss, pitting, local delamination or wear changes the finish over time. | Cleaning alone cannot replace missing material. |
Water Chemistry Can Cause Both Scale and Etching
NPC notes that excessive mineral precipitation can create scale while low pH, low calcium hardness or low carbonate alkalinity can dissolve cement compounds. That is why “calcium problem” is too vague a diagnosis: too much tendency to precipitate and too much tendency to dissolve are different chemistry conditions.
New Finish Roughness Deserves a Timeline
On a newly finished pool, record when the roughness appeared, whether plaster dust was removed, what startup procedure was followed, and the chemistry readings during the first weeks. PebbleTec warns that improperly managed early chemistry can allow white plaster dust to adhere and contribute to roughness and blotchy appearance.
Do a Whole-Pool Assessment
- Is the roughness uniform or concentrated around returns, steps, benches or the floor?
- Is it white/crusty, or does the surface simply feel etched and porous?
- Are there hollow areas or pieces coming loose?
- Did the condition change after an acid wash or chemistry event?
- Is the finish supposed to be smooth plaster or exposed aggregate?