Pool Stays Cloudy/Green

I have had my pool for three years and have let the local pool company support me with testing and advise. Lately, I have noticed they want to sell me more and more chemicals. So, I am going to start doing this myself with the help of this site.

I am attempting to get my pool summer ready. I had let it go pretty green over the winter and now have begun the process of cleaning it up. I started with the local pool company and followed their advice. That has been 1 month ago and I still can't get my pool clean. They are now recommending I put in a flocking agent and change my sand. The sand is approximately 3 years old.

I have a Pentair chlorinator that I am currently using Poolife MPT 3" tabs in.

I had the water tested today at the pool store and below are the results.
FC: 7.5
TC: 9.0
PH: 7
Alk: 64
Cal: 287
Stabilizer (CYA): 50
Copper/Iron: 0.2/0.1

I have a TF100 on order as of today, but any advice to get this moving would be appreciated.

Do I need to change sand in filter?
Do I just need to View attachment 74326 View attachment 74327 have patience and let the chemistry do it's job?



Mod Squad
LifeTime Supporter
Jan 17, 2012
Evans, Georgia
Hi there Aaron... you're on the right track. That test kit will be the key to pristine water and the use of the least amount of chemicals.

First off- Do *not* use floc nor does your sand need changing. The sand has lasted a bazillion years already, whats a few thousand more?? Floc just gums up your filter.

We do not trust pool store test results, they're wrong more often than right. So until your own test kit arrives this week I'd suggest adding a gallon of plain, unscented bleach or liquid chlorine in the pool daily and brush it. Take any pucks out of the dispenser as you do *not* want the additional stabilizer that those pucks include. Use bleach instead daily.

Then when you get your test kit run the entire set of tests and get us the results:

The pool store's metal tests are somewhat concerning. Have you or the pool service been adding any cheap algaecide that contains copper? Do you have iron in your water? How do you fill the pool, well or city water??

We've seen much worse water.... don't worry! We'll help you get it clean again!

Maddie :flower:
Thanks for the info and encouragement.

I will do as you suggest and report the test levels once the test kit arrives.

That was was the first time I have ever seen metals show up on a test report. I have not put any algecide in the pool. I do use city water to add water to the pool when necessary. After looking closer at the tablets I’ve been using, they contain 1.5% copper sulfate pentahydrate. These are new tablets that they provided that I have never used before. I’m pretty sure the ones I used to use did not contain this.


TFP Expert
LifeTime Supporter
Apr 16, 2007
Definitely stop relying on the pool store. Welcome to TFP! You and your pool will love it here!
May 10, 2017
Hays, Kansas
Throw the copper tabs away, they cause problems, don't worry pool store that recommend then will sell you something to fix that, but you will have to buy something later to fix that........

Your in good hands, no more buying stuff that doesn't work or causes problems


Mod Squad
LifeTime Supporter
Jan 17, 2012
Evans, Georgia
Still waiting on my my test kit to come in but while I’m waiting for it, I thought I would post this. I turned my pump off for a few minutes to clean the catch basket out on the pump. When I turned it back on, this blew out of the jets.

Any ideas why?

- - - Updated - - -

View attachment 74406 View attachment 74406
I'm not seeing a picture :(

Can you describe what is coming out of the returns?

Maddie :flower:


TFP Expert
Mar 2, 2011
You have been using tabs for three years and the CYA is only 50?

Do you have a lot of water replacement?

You need a full SLAM and you need to backwash and rinse more.
Here are my numbers.
FC = 4.5
CC = 0.5
pH = 7.3-7.4
TA = 110
CH = 325
CYA = 52

I’ve been adding a gallon of bleach every evening and brushing for 4 days straight.

Water is still greenish and cloudy.

The cloud coming out of my pump did stop very shortly after restart.

Any help is is greatly appreciated.

x Wild Bill x

Well-known member
May 5, 2016
Rochester, MA
Do you have your TF100 test kit and were you able to confirm your CYA of 52? Reason I ask is the test only has gradient readings in increments of 10 so a reading of 52 is not possible without guessing. Since it is not a linear scale, the experts here recommend rounding up to be safe. The CYA test is the one the pool $tore gets wrong most often so I would make sure you have run your own CYA test before starting your SLAM or you may just be spinning your wheels.


Mod Squad
TFP Expert
LifeTime Supporter
May 11, 2014
Franklin, NC
Yea, 52 is a pool store type CYA result. If you don’t have your TF-100 yet it will basically be impossible to start the .

You need good baseline numbers and correct testing so you add the correct amount of chlorine to keep the FC at shock level all day. Hopefully you ordered the XL option because you will be testing the FC a bunch of times each day....
I do have my test kit and the numbers I gave regarding the CYA was a guess. Thanks for letting me know to round up. I will do that from now on. I started the SLAM process last night. According to my second CYA test, I was just below 50 so I rounded up to 50.
I have been following the calculator to add the appropriate amount of bleach.
Overnight, I went from FC of 20 to FC of 14.5. I added enough bleach to achieve FC of 20 again before work. When I got home around 3, I tested the water and was back down to FC of 15. I have brought the level back to 20 and will likely check one more time before bed.

My water looked mich bluer today until I brushed the pool and stirred up crud from the bottom. I will vacuum the pool tomorrow.

Any suggestions as I continue the SLAM process?