New pool startup chemicals and test kit on a daylight deck

Pool Care 101: The First 30 Days After Installation

Just had a pool installed? The first 30 days are critical — the curing plaster needs careful chemistry, the system needs to be balanced for the first time, and small mistakes now can leave permanent marks on the surface. Here’s the day-by-day plan to get from “pool’s done” to “safely swimmable, properly balanced, and ready for the season.”

Days 1–7: Plaster cure period (if you have a plaster pool)

Fresh plaster releases calcium hydroxide into the water for the first 7–14 days. The water will turn slightly cloudy, pH will spike high (often 9.0+), and tiny calcium dust will settle on the floor. This is normal.

  • Brush the entire pool surface twice a day for the first week with a soft nylon brush (steel bristles can damage uncured plaster).
  • Test pH twice daily and add muriatic acid or dry-acid pH reducer to bring it down toward 7.4–7.6.
  • Don’t add chlorine until day 3–5; plaster contractors will guide you on timing.
  • Don’t use a vacuum until day 14 — calcium dust will settle, then you can clean it.

Days 8–14: First chemistry pass

By the end of week 2, the plaster has stabilized enough for a real chemistry routine:

  1. Test all six parameters: free chlorine, pH, total alkalinity, calcium hardness, cyanuric acid (stabilizer), and salt (if applicable).
  2. Bring alkalinity into the 80–120 ppm range first (alkalinity stabilizes pH).
  3. Then adjust pH to 7.4–7.6.
  4. Bring calcium hardness to 200–400 ppm (most fresh pool water is below this).
  5. Add stabilizer to reach 30–50 ppm (60–80 for salt pools).
  6. Finally, add chlorine. Target 2–3 ppm free chlorine.

Doing this in order matters. Adjusting chlorine first when alkalinity is wrong is a waste of chemical.

Days 15–21: Equipment break-in

  • Read your filter’s clean baseline pressure and write it on the housing.
  • Confirm pump prime is solid (no air in strainer pot).
  • Run a salt cell or chlorinator and verify chlorine output stays in target range.
  • Set the pump timer / variable-speed schedule to 8–12 hours of runtime per day.
  • Brush the entire pool once a week from here forward.

Days 22–30: Routine settling in

By day 30 you should be running a stable weekly maintenance routine: 2–3 chemistry tests per week, weekly brushing, basket cleaning, and a backwash or filter clean when pressure rises 8–10 PSI above baseline. If chemistry is still drifting wildly, something’s wrong — usually undiagnosed high cyanuric acid suppressing chlorine effectiveness, or stabilizer added before alkalinity was balanced.

The starter chemicals every new pool needs

What to NOT do in the first 30 days: dump a giant chlorine shock in (a fresh plaster pool is reactive and you’ll get stains); add stabilizer before alkalinity; vacuum during the calcium dust phase; or skip brushing.

Reach out to PST Pool Supplies if you want a customized starter chemical package matched to your pool size and finish type — we’ll bundle exactly what you need for the first 30 days at a bundle price.

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