Help ! Cannot hold Free chlorine levels!!


New member
Jul 5, 2020
West seneca , NY
Someone please help me I’m at a total loss what to do next! First year with my Inground pool it’s about 16,500 gallons SWG. About 3 weeks ago I dealt with phosphates and algae did 2 treatments . Phosphates level are down to 250 great! Well I still can’t hold a free chlorine reading for the life of me: I super Chlorinate and it reads a reading then within 24hrs it’s gone again!! Just got my water tested it’s
free chlorine- .31 ppm
Total chlorine - .77ppm
Combined chlorine - .46
pH- 7.8
Hardness - 107
Alkalinity- 86
CA- 19 (just added a little stabilizer to up this )
Phosphate - 200
Salt 2685 but my app said 2860

I shocked pool twice also one past 2 weeks

also let me add when I vacuum the pool the jets turn soooo Milky cloudy! But after the pool is clear !


Mod Squad
TFP Expert
Bronze Supporter
May 3, 2014
Laughlin, NV
Welcome to the forum!
You need to follow the SLAM Process. To do that, you need a proper test kit. I suggest the TF-100 A proper test kit is needed to get the accurate water chemistry results needed to follow the TFP protocols. I suspect the data you show above is from a Pool Store.

While you are waiting on your test kit, add 5 ppm FC worth of liquid chlorine / plain bleach to your pool each evening with the pump running. This will replenish the FC lost each day to the sun and also inhibit any algae in the water from growing further.
I suggest you read ABC's of Pool Water Chemistry.


Well-known member
Dec 31, 2019
Houston, Texas
What % do you run your SWG and how many hours per day? What model of SWG do you have?

After you get your test kit, post how much CYA you have. I think you have fallen into the trap of listening to the pool store and buying a lot of unnecessary chemicals. For example, phosphates are rarely an issue in a pool, but pool stores love to sell phosphate reducing chemicals.

And to repeat the advice above, get an accurate test kit and, in the meantime, add liquid chlorine asap daily. 5 ppm worth per day.


Mod Squad
LifeTime Supporter
Jan 17, 2012
Evans, Georgia
SWGs work very slowly.....steady like a tortoise. But if you have something funky in the water you need to treat it with LIQUID chlorine for an *immediate* blast of Free Chlorine (FC), and then maintain that desired level until the funk is gone fo'eva!

We call this a SLAM Process= Shock Level and Maintain. It requires a good test kit that gives you these results:

Liquid chlorine is simply chlorine with none of the other chemicals in it like calcium or extra stabilizer which can cause build up problems. Then you need a certain. amount of CYA Stabilizer to hold your chlorine in. the water- BUT NOT MORE THAN A CERTAIN AMOUNT! Hence the use of liquid chlorine during the SLAM only. Then follow the FC/CYA chart to keep your water sanitary.

Read please: ABCs of Pool Water Chemistry
SLAM Process
FC/CYA Chart

Holler with questions :)

Maddie :flower:


Mod Squad
LifeTime Supporter
Jan 17, 2012
Evans, Georgia
FYI- 20 ounce of Walmart 10% Pool Essentials liquid chlorine gives your 16,000 gal pool 1 ppm. FC
So I'd put a full gallon of the 10% in daily and brush untill your test kit arrives.

The classic web version of PoolMath gave me these numbers. Play around with it :). PoolMath

Maddie :flower: