Pool Era field notes · Finishes and renovation

The First 28 Days After New Pool Plaster

Just had your pool built or replastered? The next four weeks matter. The finish is still curing under the water, and small mistakes now can show for years.

Here is what the industry's start-up steps ask for, in plain words.

By the Pool Era teamUpdated October 25, 2026Sources due for re-check April 2027How we research and fact-check

Why it matters

The finish is still curing.

The National Plasterers Council (NPC) says a pool's interior finish is especially likely to stain, scale or discolor in the first 28 days.[1] National Pool Tile, a finish maker, says 86% of the cement in plaster cures in those first 28 days.[2]

Fill day

Fill it all at once.

Wrap a clean cloth on the hose end and lay it in the deepest spot, so the water does not mark the surface.
Fill to the middle of the skimmer without stopping, as fast as you can, with clean drinking water. NPC says this helps prevent a bowl ring and shrinkage cracks.
Keep people and pets out of the pool while it fills.
Start the filter system as soon as the water reaches the skimmer.[1]

Week one

Brush, test and wait.

Brush the whole surface at least twice a day to lift plaster dust.
Run the pump and filter nonstop for seven days, or until the dust is gone and the water is clear, and at least 72 hours.
Test pH, total alkalinity and calcium hardness every day and adjust them in the order the NPC card lists.
No chlorine for the first 48 hours. Do not turn on the heater until the plaster dust is gone.
No wheeled vacuums or wheeled pool cleaners for 28 days. Brush vacuums are fine.[1]

Weeks two to four

Keep the water balanced.

Keep pH and alkalinity in range every day.
Raise calcium hardness slowly, to at least 200 ppm, if it is low.
Add stabilizer (cyanuric acid) slowly through the skimmer, starting around day four, and brush after each dose.
Salt pool? NPC says do not add salt for the first 30 days.
After the dust is gone, brush when you see dirt or when you add chemicals.[1]

NPC does not recommend swimming until the water is properly balanced and sanitized.[1] Ask your builder when swimming can start in your pool.

Hill Country water

Hard fill water changes the plan.

NPC says very high or very low calcium hardness, pH or alkalinity in the fill water may mean the start-up steps need to change.[1] The San Antonio Water System says its typical hardness is 15 to 20 grains per gallon.[3] Test your fill water on day one, before you add anything.

Ask your builder or plasterer who handles start-up, and get the steps in writing.

Talk to us about plaster

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Sources

Where these facts come from

Sources checked October 25, 2026. Rules, fees and water stages change; check the source before you rely on a number.

Who wrote this

Pool Era team. Pool Era builds, refinishes and cares for pools in the Texas Hill Country, and the founder supervises the work on site. We write field notes from public agency, trade group and maker sources, cited on the page, plus what we see on local jobs.

Sources checked October 25, 2026. Next scheduled check: April 2027. Spot an error? Tell us and we can check it against the source. Our editorial standards

Before you rely on this. This field note is general information, not professional, engineering or legal advice. Every pool and every site is different. What Pool Era does on your project, how and with what warranty, is only what your written agreement says. Local codes and HOA rules change, so check with your city, county or HOA before you rely on anything here. Website terms

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