Pool Water Troubleshooter
Answer one or two questions about what the water looks like and get the diagnosis, the fix in order, and an honest line on when it stops being a DIY job.
Green water is almost always an algae bloom that started when free chlorine hit zero. Cloudy water without any green is usually filtration or balance, not algae. Brown water and clear-but-tinted water usually mean dissolved metals, and a pool that reeks of chlorine needs more chlorine, not less. The color and clarity of the water narrow the cause fast, which is what this tool does.
What does the water look like right now?
Look at the pool in daylight, after skimming any debris off the surface.
Guidance current as of August 2026
The three habits that make any recovery work
Order matters more than effort. Shocking a pool with pH at 8.0 wastes most of the chlorine you just paid for, so every plan above starts with pH near 7.2 before any chlorine goes in. Alkalinity buffers pH the same way, which is why it gets balanced before pH does.
One product at a time. Add it with the pump running, give it at least 20 minutes to circulate, and retest before the next dose. Never mix chemicals with each other, and never combine chlorine and acid in any form.
The filter does half the work. Chemistry kills algae; filtration removes it. Almost every recovery on this page involves running the pump around the clock and cleaning the filter each time pressure climbs 8 to 10 psi over its clean baseline, and skipping that half is the usual reason a recovery stalls.
Dose for your actual gallons
Every dose scales with pool volume, and most people only have a rough idea of theirs. The volume calculator takes your dimensions and returns the gallons, then sizes each chemical dose to match, from the same figures our store and service techs use. Two pools that look the same size can differ by a third of a dose just from the depth of the deep end.
Keep reading
Pool Water Problem Questions
Because the shock worked. Cloudy grey-blue water after shocking a green pool is dead algae in suspension, and no further chemical will clear it. Run the pump around the clock, clean or backwash the filter each time pressure rises 8 to 10 psi over its clean baseline, and give the filter two to four days to catch it all.
A strong chlorine smell means the pool needs more chlorine, not less. The odor comes from chloramines, which form when chlorine combines with sweat, sunscreen, and other organics and stops sanitizing. The fix is a shock at dusk strong enough to break the chloramines apart. The smell is gone when free and total chlorine test nearly the same.
Brown or tea-colored water is usually dissolved iron oxidizing, and it often shows up right after a shock or a fill from well water. Shocking harder makes metal staining worse. Hold your normal chlorine level, confirm with a metals test, and use a metal sequestrant to keep the iron in solution and off your liner.
Water full of algae and organics consumes chlorine as fast as it goes in, so a zero reading shortly after dosing means the demand has not been met yet, not that the test is wrong. Keep dosing to shock level until chlorine finally holds overnight. If it never holds even in clear water, test stabilizer: both very low and very high CYA make chlorine ineffective.