Cloudy/green pool


New member
Apr 24, 2019
I have a 22x52 above ground pool with a intex sand filter. I didn’t have it covered through the winter. I have scrubbed the floor/walls, got all the debris out I can, vacuumed the floor, and shocked it multiple times. The water started off dark green/brown. After shocking it, it turned cloudy and then halfway clear but still had dirt on the floor. I vaccummed the floor again and then the water turned green. I have shocked it and got the chlorine levels up and the water is now milky. I noticed today there was debris settled On the floor in spots as the water was darker. I vacuumed the spots and the water turned green again and debris floated to the surface. What do I do to keep the water from turning green every time I vacuum?? Any ideas on a good way to vacuum small debris?


Gold Supporter
TFP Guide
Jul 21, 2013
Northern NJ
Pool Size
Salt Water Generator
SWG Type
Pentair Intellichlor IC-60
Welcome to TFP.

We don't use shock because it is insufficient to kill all the algae as you haev discovered. What it does do is keep people coming back to the pool store to buy more.

We have the SLAM Process process that has you increase your CL to shock levels and MAINTAIN it there until the algae is killed. To do the SLAM Process process you need your own test kit - either the TF-100 Test Kits or the Taylor K-2006C. See Test Kits Compared. I also suggest you get the Speedstir Magnetic Stirrer which makes testing easier and more accurate.

I suggest you read ABCs of Pool Water Chemistry and Pool School - Trouble Free Pool

Post here with any questions and post your test results once you get your test kit.
  • Like
Reactions: setsailsoon


Bronze Supporter
Aug 2, 2017
SE Kansas!
Welcome fellow Kansan!
... I have shocked it and got the chlorine levels up ...
The "shocks" are either adding calcuim or CYA (stabilizer), neither of which are good in excess, calcuim is not necessary for Vinyl, above or in-ground.

You can get a "baby/starter" HTH drops test kit at Walmart while you wait for full test kit to arrive (which must include the FAS-DPD and CYA tests)

Skim the Pool School articles, TFP and the forum members can offer lots of money saving experience and 'support'!
Last edited:


TFP Expert
LifeTime Supporter
Jan 6, 2010
San Dimas, CA (LA County)
Welcome! :wave:

What's happening is that you're not following-through. An algae bloom is a battle to the death. You knock it down but then allow it to build back up. You need to knock it down and then kick it again and again and again. We call the process the SLAM Process

There are some links to older threads showing what we mean here. The newer ones are last.


Gold Supporter
LifeTime Supporter
TFP Guide
Oct 25, 2015
Pool Size
Salt Water Generator
SWG Type
CircuPool RJ-30 Plus

You're not killing all the algae. Shock kills a bunch of algae 'till it's all consumed then the algae goes on another romp. Soon after you shock the algae is re-growing faster than you're taking it out in the clumps of debris. This cycle will repeat over and over until your pool store says you need more expensive algaecides that are almost never really required and can cause you other problems. This is why TFP uses a SLAM which is a process that maintains level of FC that it kills all the algae until it is all dead. This often takes more chlorine initially and persistence of frequent testing but it always uses the least possible total amount and gets the mess completely back to sparkling in the shortest possible time. Done right this process takes days not weeks and it's by far the cheapest solution.

You have experienced experts already engaged here to advise you every step of the way. Just ask any questions you have, follow their advice and you'll have this behind you in no time!

Good luck.

Thread Status
Hello , There was no answer in this thread for more than 60 days.
It can take a long time to get an up-to-date response or contact with relevant users.