Green pool fix: what a real pool pro will (and will not) do
The difference between a $180 green pool shock and a $900 algae disaster is usually one thing: whether the pro checks the filter before dumping chemicals in.
Every April we get calls from homeowners with the same problem: the pool looks like pea soup and a pro on the phone just quoted $900 for a 'full algae remediation with drain and acid wash.' Sometimes that is the right fix. Usually it is not. Here is how to tell the difference.
A good pool pro diagnoses before they dose. The first thing a real pro will do is check the circulation — specifically the filter pressure and the pump basket. If the filter has not been cleaned in six months and the pressure is high, water is not moving, and no amount of shock will clear an algae bloom that the filter cannot trap. Adding chlorine to a pool with dead circulation just turns green water into green water with bleach in it.
A good pro will also test the free chlorine and the cyanuric acid before quoting. Cyanuric acid (sometimes called conditioner or stabilizer) binds chlorine. If your cyanuric acid is above 80 ppm — which happens to a lot of pools that use stabilized tablets for years without a partial drain — you can dump five gallons of liquid chlorine in and still not get a kill-level free chlorine reading. The fix there is to drain 25 to 40 percent of the water, not to pour more chemicals on the problem.
What a real pro will not do: start by recommending a drain-and-acid-wash. That is the most expensive fix in the book and it is almost never the right first move. Draining a pool in Southern California in summer is risky — the hydrostatic pressure can crack the shell if you have a high water table, and you lose all the stabilizer you paid for. An acid wash strips plaster. A good pro will only go there after a shock cycle and a filter clean have actually failed, and they will explain why.
What a real pro will do: explain the diagnosis in plain English, quote a shock-and-clean at somewhere between $180 and $320 for a standard residential pool, warn you if the fix might take a second visit, and only escalate to the expensive options if the cheap ones do not work. If the first thing a pro quotes is the most expensive thing on the menu, get a second opinion.
This is exactly the kind of call HiredLocalPros exists to route well. When our AI matches a homeowner to a pro, we weight the match by two things: whether the pro has CSLB C-53 pool service credentialing and whether they have a transparent quote history. The pros at the top of our Top 10 lists are the ones most likely to give you the cheap fix first and earn the expensive fix later.