Cloudy water after a refill: normal, or a problem?

Cloudy water in the days after a refill or an acid wash worries people more than it should. It is usually normal, it is usually chemistry, and it usually clears itself with the filter running.

Here is what is actually happening and what shortens it.

Why fresh water goes cloudy here

Valley fill water is hard and unbalanced. It arrives carrying a lot of dissolved calcium and it is not at the pH or alkalinity your pool wants. Out-of-range water is the single most common cause of cloudiness, and high pH combined with high calcium hardness will cloud a pool on its own by pushing calcium out of solution.

New or freshly washed plaster is chemically active. A surface that has just been acid washed is raw. It releases material into the water for a period and it changes the water chemistry while it does, which is why the first week after a wash needs attention rather than being left alone.

The filter is doing a lot at once. A refill puts fine particulate through the system in quantity.

Dust. This is Arizona. A windy day or a monsoon storm puts a measurable amount of fine material into an open pool, and fine dust is exactly what makes water hazy rather than dirty.

The order that clears it fastest

Order matters, and doing this out of sequence is why some pools stay cloudy for a fortnight.

1. Run the filter continuously. Not on a timer, not eight hours. Continuously, until it clears.
2. Get total alkalinity in range first, then pH. Because alkalinity is what holds pH steady, fixing pH before alkalinity just sends you chasing it.
3. Then chlorine.
4. Then check calcium hardness. If it is very high on a fresh fill, cloudiness may persist and the long-term answer is managing the water rather than treating the haze.
5. Brush the walls and floor daily. This puts settled material back into suspension where the filter can catch it, and it matters more than people think on a new surface.
6. Clean or backwash the filter once it has been working hard, then again a few days later.
7. Only then consider a clarifier or flocculant. They work, but on balanced water. On unbalanced water they treat a symptom you are also still creating.

Aftercare on a freshly acid washed pool

If your pool has just been washed, the first week matters:

• Keep the filter running continuously for the first few days.
• Test daily, not weekly. A raw surface moves the chemistry around.
• Brush daily.
• Expect some dust film on the floor initially, and brush it rather than worrying about it.

Water balanced properly in that first week is also what protects the new surface. Leave newly exposed plaster sitting in aggressive water and it etches, and that undoes the wash you just paid for faster than anything else.

When it is not normal

Call someone if:

• It is still genuinely cloudy after a week of continuous filtration and in-range chemistry.
• It is cloudy and getting greener, which is an algae problem rather than a clarity problem. See pool turned green.
• The filter pressure is high or the returns are weak, which points at the filter rather than the water.
• The water is milky white and will not respond at all, which on a fresh fill often means calcium out of solution.

What it costs

Most of this costs nothing beyond chemicals and patience, which is why the page is written this way. Where it turns into work:

From the pricing page.

Get a quote

If a just-washed pool is not clearing, call the crew that did it; a fair one will talk you through the chemistry on the phone rather than charging a visit for it. We cover Mesa, Gilbert, Chandler, Tempe, Apache Junction, Queen Creek, and Gold Canyon.