Cloudy Salt Water Pool

[Munson1897]

Hi,

I've been a salt water pool owner for over two years and I'm recently having difficulty with the cloudiness of my pool. The pool is 21,100 gallons, and I have a Hayward DE Filter. Just installed a new Hayward variable pump at the beginning of last year. The SWG is turned on to 76%.

I opened the pool on Saturday, (June 6th) and as usual, the water was dark green with lots of dirt on the bottom. I balanced the required chemicals and added Power Plus shock (two bags) to the pool. As the week went on it became clearer (80% blue) and completely visible with the exception of the remaining dirt at the bottom of the pool. My Alkalinity, Calcium, CYA, Salt and PH levels were all well within recommended range (although PH was 7.8), but for the first time in three years, I registered 0 FAC. I found that odd as I've always had some traces (1-1.5) FAC in the pool.

On Wednesday (June 10), when I came home from work, the entire deep end of the pool was murky and the shallow end was partially cloudy. I brought a water sample to Leslie's and the manager said I didn't need FAC in my pool since it's salt water. The other gentleman working seemed puzzled at the manager's response, as he initially suggested adding shock to the pool to raise it. The manager suggested adding Ultra Bright to improve the clarity of the pool. I went home and backwashed, since the PSI was 8 over the normal level and added the Ultra Bright. I let the filter run over night and checked it out the next morning. The water is still incredibly cloudy, the FAC is still 0 and the PSI went up another 6-8. I backwashed the filter again, replaced the DE and added a second dosage of Ultra Bright.

My question is this: Is the reason why my pool is so cloudy/murky because I haven't given it enough time to clear up on its own, as the drain at the bottom o the pool is still filtering out all the remaining dirt, or is it because I have 0 FAC in my pool? I've only had the pool open five days.

Thank you

 

[woodyp]

There is a wonderful article in Pool School regarding SLAMming your pool, which is required. There is another there on how to properly close your pool for the winter and avoid opening to a swamp in the spring. (Psssst......you'll need one of our recommended test kits).

 

[poolnoob.ca]

I brought a water sample to Leslie's and the manager said I didn't need FAC in my pool since it's salt water. The other gentleman working seemed puzzled at the manager's response, as he initially suggested adding shock to the pool to raise it. The manager suggested adding Ultra Bright to improve the clarity of the pool.

That's why TFP says "stay out of the pool store", ridiculous advice and unneeded chemicals.

But a few questions, 2100 or 21000 gallons?
Do you have your chlorine generator turned on? How much chlorine have you added and what type?
What test kit did you use? We need numbers, not "within range".
It sounds like you need to do the SLAM process

 

[Texas Splash]

Hello and welcome to TFP! We can help (if you let us) to get your water to where it needs to be. But here are a few basic TFP principles:
- If you haven't done so already, make sure you get one of the recommended test kits (i.e. TF-100 below). An absolute “must” to obtain the proper chemical readings needed. The proper test kit is everything. Why? Because we've all learned (from personal experience) you cannot reply on pool store tests, test strips, or simple over-the-counter kits. They don't read Free Chlorine (FC) or Cyanuric Acid (CYA) levels accurately or to the high levels we need.
- Golden rule - Avoid the pool store for testing, advice, or products. You simply won’t get the advice/service you deserve and you will waste money on products your pool doesn’t need. Do not add anything to your pool other than what is advocated by the TFP site or its experts.
- Please understand the TFP method does not simply "shock" or "super-chlorinate" a pool as typically advised by the local pool store. We do what's called "SLAM". SLAM is significantly different than an overnight “spike” in chlorine, and can take a few days (perhaps even a week or two) to properly complete. The recommended test kit is extremely important to properly conduct a SLAM.
- Also, please add your pool info to your signature by going to the top of the TFP web page (just under the Pool School button) and select "SETTINGS". On the next page look to the left for a menu bar that says, “MY SETTINGS” and go to "EDIT SIGNATURE" to enter your pool and equipment info there. It will help us later.

At this point, I would not put anything else in your pool other than regular liquid bleach - about 1/2 gallon per day until you get the test kit. When you get your kit, post YOUR OWN numbers for us (FC, CC, PH, TA, CYA and CH). Also, in the meantime, try to keep your PH at 7.2 since that's a prerequisite for the SLAM process.

Welcome!

 

[Munson1897]

Thank you for your response. Yes, sorry the pool is 21,100 gallons

I have the SWG turned on to 76%.

PH = 7.8
ALK 120
CYA 60
Calcium 220
Salt 3200
FAC 0

I guess the main question I have is the necessity of FAC for a salt water pool. I always felt you needed to have traces of it (1.0 - 1.5) in the pool. Am I wrong?

 

[Texas Splash]

Actually whether or not you have a SWG, your FAC should be at the appropriate level as noted on the Chlorine/CYA chart (link below). You have no free chlorine which is a breeding ground for algae/bacteria. If your water was perfect, the target level for CYA of 60 would be 4 FC ppm. When your water is clear and healthy, your SWG should produce the appropriate amount of sanitizer to do that. But when your water is cloudy, green, or otherwise showing indications of algae, your SWG will not be able to maintain the required FC level to kill the algae. That's why you will typically see TFP recommended to SWG users to dial down their SWG and augment the "SLAM" process with bleach.

Based on your readings provided, and the fact your water is cloudy, you are a good candidate for "SLAM". So if you are going to follow the TFP method, here's what you need to do:

- Reduce PH to 7.2 if possible (no more than 7.5)
- With CYA at 60, you need to meet an FC SLAM level of 24. Use the Chlorine/CYA chart (link in my sig) to add regular liquid bleach and bring your FC up to the proper SLAM level rating of 24 which is based on your current CYA of 60 and make sure it stays there (MAINTAIN) until you meet ALL 3 SLAM criteria! That may take just a few days or even a week or two! That is absolutely critical for success.

The Poolmath Calculator (link below) is a perfect tool to help you confirm the amount of each product required to meet those levels. I suggest you start right away, however you must have a TF-100 or Taylor K2006 test kit. Pool stores, test strips, and/or local over the counter kits will not give you readings at these levels.

- - - Updated - - -

At the same time, continue to run your pump 24/7. Remove any “muck” and debris, scrub all parts of your pool to expose any algae, and vacuum/clean (or backwash) filter as necessary. You may have to do this several times. It's a lot of babysitting, but with patience and consistency, you will succeed.