Do I need to SLAM my pool?

[alex800]

Hi, the last week or two I noticed my pool is a bit cloudy in the mornings. FC is about 2.0 in the morning but by the end of the day, the water is crystal clear with SWG running for about 10 hours. In the evening FC is about 4.5 - 5. So it looks like I'm losing 2-3PPM per night. is it normal? Do I have a problem with my water? This is my first summer with a new pool and I was doing OK until now. This is 11K gal pool and I'm run the pump for 11 hours during the day.

CYA 80
pH 7.7
TA 85
CH 370
Salt 3400
Water temp 87

TIA

 

[Texas Splash]

So it looks like I'm losing 2-3PPM per night.

That's not good. A loss of more than 1 ppm overnight confirms the need to perform the SLAM Process. In addition, if you look at the FC/CYA Levels for a salt pool you can see your FC of 2 was well below the minimum and daily ideal ranges to prevent algae. That explains the cloudy water and excessive loss of FC.

 

[alex800]

So SLAM it, run SWG longer or add liquid chlorine to bring CF higher?

If SLAM how much of liquid chlorine do I need? Can I use Clorox bleach? I never did that before.

 

[Texas Splash]

SLAM. Use the PoolMath APPs "Effects of Adding" to help show you how much chlorine is required to increase the FC to the proper SLAM level. A CYA of 80 requires an FC of 31. You'll rely primarily on liquid chlorine for that since SWGs are not designed to produce that much chlorine. Do not use the Clorox brand laundry bleach. You can use other brand of laundry bleach, but make sure they are not splashless or scented. You want the regular/plain stuff. Remember laundry bleach is a lower strength (about 7%), so if you can get Pool Essentials from Walmart or HDX pool chlorine from Home Depot (10%) those might be a better value for you. Don't forget to lower the pH to 7.2 before increasing the FC. Follow all the details of the SLAM page and you should do fine.

 

[alex800]

Not able to find LC. Just tried Lowes, HD and WM.

 

[Newdude]

Pinch a penny, hardware stores, ocean state job lot…. Most pool stores

 

[Texas Splash]

Not able to find LC. Just tried Lowes, HD and WM.

Might have to be regular laundry bleach then.

 

[alex800]

Just tried another WM and it has it.

 

[Texas Splash]

 

[alex800]

I'm a little confused on the SLAM process. It says I need to bring up FC to 31ppm which is approximately 3 gal for my pool. What's next? Do I run the pump for 24 hours constantly checking FC to make sure it is at 31PPM for the next 24 hours? Is the goal to maintain 31ppm for at least 24 hours and then test for overnight chlorine loss? My water is not that bad so it will be hard to tell visually.

 

[Texas Splash]

Do I run the pump for 24 hours constantly checking FC to make sure it is at 31PPM for the next 24 hours? Is the goal to maintain 31ppm for at least 24 hours and then test for overnight chlorine loss?

Yes, the pump remains on at all times. Low speed is fine. No need to do the Overnight Chlorine Loss Test until the last step once the water is 100% crystal clear. In the meantime, you check the FC periodically through the day to try and maintain that FC of 31. If it holds fairly well it won't be too difficult to do. Be sure to follow all the SLAM cleaning tasks and hopefully you'll get through the SLAM in a good timeframe. But maintain the FC of 31 until you pass all 3 SLAM criteria.

 

[Newdude]

I'm a little confused on the SLAM process

No, sir. You are not. You have it *exactly*.

You will S-L-A-*Maintain* your target FC for as long as it takes, as often as it takes. 2 hours is great between tests/adds. If life gets in the way a little, do your best.

 

[alex800]

Well the reason I'm confused is because my water is not looking bad. It's just I noticed an overnight chlorine loss between 2 and 3 ppm.

So after 24 hours of SLAM test for OCLT?

Here is how my water looks right now.

 

[Texas Splash]

It's just I noticed an overnight chlorine loss between 2 and 3 ppm.

That alone is a reason to perform the SLAM. Too much FC loss. Maintain the SLAM level until the water is crystal clear to the deep end. Once you have achieved perfect clarity, then do the OCLT. If you fail another OCLT, you have algae hiding somewhere in the pool.

 

[alex800]

That alone is a reason to perform the SLAM. Too much FC loss. Maintain the SLAM level until the water is crystal clear to the deep end. Once you have achieved perfect clarity, then do the OCLT. If you fail another OCLT, you have algae hiding somewhere in the pool.

So I started yesterday around noon. Brought the pH down to about 7.2. Added 3.3 gal of LC. Test first time in a an hour and FC was around 35ppm. Throughout yesterday and this morning I added another 3 gal because FC is constantly drops. By the way it was raining heavy yesterday evening. My testing results are in my signature.

 

[Texas Splash]

It looks like you dropped from about 30 to 21 overnight correct? So you definitely have an algae issue. Continue with the SLAM Process. Try to maintain the ideal FC level of 31 based on your CYA of 80. At the same time, don't rely solely on the chlorine. Be sure to brush everywhere and inspect closely ANY potential hiding areas in the water (steps, ladders, behind lights, etc). Leave nothing to chance that the chlorine needs to reach.

 

[alex800]

It looks like you dropped from about 30 to 21 overnight correct? So you definitely have an algae issue. Continue with the SLAM Process. Try to maintain the ideal FC level of 31 based on your CYA of 80. At the same time, don't rely solely on the chlorine. Be sure to brush everywhere and inspect closely ANY potential hiding areas in the water (steps, ladders, behind lights, etc). Leave nothing to chance that the chlorine needs to reach.

It was 30 PPM last night and I added 42oz of LC. This morning I tested around 7am and it was 21 so I added another 169oz. per TFP app. I don't know what's happening. The water looks clear to me. Maybe be a little haze in early AM. I brushed yesterday all the walls and steps and did not notice anything unusual. Can it be something inside the umbrella hole? The pool is not that big.

 

[Texas Splash]

The water looks clear to me.

Algae can be deceiving. Certainly check the umbrella sleeve and anything in the pool where water can get trapped. Something is hiding and the FC is being consumed by it. Algae in it's early stage is transparent so you will be puzzled as to why, but it's there.

 

[alex800]

Algae can be deceiving. Certainly check the umbrella sleeve and anything in the pool where water can get trapped. Something is hiding and the FC is being consumed by it. Algae in it's early stage is transparent so you will be puzzled as to why, but it's there.

Cleaned umbrella sleeves. Still adding chlorine throughout the day. Over 7 gal since yesterday. Only 1 gal have left.

 

[Texas Splash]