How to Clear a Green Pool: A Step-by-Step Plan That Actually Works
Green water is algae, and algae loses to sustained chlorine. Here is the exact process — test, shock to the right level…
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Green water, cloudy water, chlorine that won't hold, a pump that won't prime — get plain-English fixes with pro-level detail, plus the calculators to get the dose right the first time.
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Water Chemistry
Chlorine, pH, alkalinity, stabilizer and salt — what every number means and how to move it.
3 guides
Cleaning & Care
Weekly routines, openings, closings and the habits that keep water clear with less work.
4 guides
Problems & Fixes
Green water, cloudy water, algae, stains, leaks — diagnosed and fixed step by step.
4 guides
Equipment
Pumps, filters, heaters, cleaners and salt cells — how they work and what to buy.
4 guides
Surfaces & Coatings
Plaster, pebble, tile, paint and spray-applied coatings for pools and decks, compared honestly.
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Container Pools
Shipping container pools from steel box to backyard — cost, build, finishes and the business behind them.
2 guides
Pool math, done for you
Stop guessing how much to add.
Find your gallons, dose chlorine and balancers precisely, and see exactly where your chlorine should sit for the stabilizer in your water.
Ideal water, at a glance
The seven numbers that keep a pool clear.
Hit these ranges and most pool problems never start. Each bar shows the sweet spot inside the full test range.
Free chlorine
1–4 ppm
pH
7.4–7.6
Total alkalinity
80–120 ppm
Calcium hardness
200–400 ppm
Cyanuric acid (CYA)
30–50 ppm
Salt (salt pools)
2,700–3,400 ppm
Combined chlorine
0–0.2 ppm
Most-read guides
What pool owners ask us most.
Pool Water Chemistry 101: The Seven Numbers That Matter
Free chlorine, pH, alkalinity, calcium, stabilizer, salt and combined chlorine — what each number does, the range to aim for, and how…
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Cloudy Pool Water: 9 Causes and How to Fix Each One
Hazy, milky or dull water almost always traces back to chlorine, chemistry or filtration. Work through these nine causes in order and…
Read guideShipping Container Pools: The Complete Guide to Cost, Build and Finishes
Everything to know before you buy or build a shipping container pool: sizes, realistic costs, how they are built, interior finishes and…
Read guideThe Weekly Pool Maintenance Checklist Pool Techs Actually Use
A 30-minute weekly routine that keeps water clear and equipment healthy — plus the monthly and seasonal checks most owners forget.
Read guidePool Shock Explained: Liquid Chlorine vs. Cal-Hypo vs. Dichlor vs. Non-Chlorine
All "shock" is not the same. What each type adds to your water besides chlorine, when to use which, and the side…
Read guideFor contractors, fabricators & entrepreneurs
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Ask your questionHow often should I test my pool water?
Test free chlorine and pH two or three times a week (daily during hot, heavy-use stretches). Test alkalinity, calcium hardness, stabilizer (CYA) and salt about once a month.
What chlorine level should my pool be?
Most outdoor pools do well at 3–5 ppm free chlorine, but the right minimum depends on your stabilizer: keep free chlorine at least 7.5% of your CYA level. Our chlorine & stabilizer chart does the math for you.
Why is my pool green even though I added shock?
A single dose rarely clears algae. You need to raise chlorine to shock level for your CYA and hold it there — testing and re-dosing several times a day — until the water is clear and chlorine holds overnight.
How long should I run my pool pump?
Long enough to filter the whole pool volume about once a day. With a variable-speed pump, running at a low speed for more hours is usually the most efficient way to get there.
Is a saltwater pool chlorine-free?
No. A salt chlorine generator makes chlorine from dissolved salt. The water is much less salty than the ocean, and you still need to manage pH and stabilizer.