To drain or not to drain

[pool4mykids]

30000 gallon saltwater pool which is 10 years old. Opening this year water will not clean up from cloudy condition. I am struggling weather to drain, or partial drain.

Initially opening
FC 2.0
CC 4.5 WOW!
ph 7.2
TA 50
CH 80
CYA Undetectable
Salt 3500
Complete vacuum and sweep multiple times with pump running 24 hours a day. I added 6 gallons of 7.75% bleach over 48 hours but FC will not rise to SLAM # 0f 10.

I have always been able to get the pool started in one-two days without issue. Water is NOT green, but I can see bottom is shallow only. I suspect I may have ammonia ? One dead squirrel was in the deep end. Please advise

28000 gallon in ground vinyl
Hayward goldline aquarite
Hayward sand filter
1.5hp single stage pump

 

[ajw22]

FC will be 0 if you have ammonia. To determine if your pool will hold chlorine add 10 ppm of liquid chlorine and test your FC in 30 minutes. If you have over 4 ppm of FC then you don't have ammonia.

Just sounds like you have an algae problem and need to follow the SLAM Process. Even if you do a drain you will need the SLAM Process for whatever residual algae remains in the water.

 

[pool4mykids]

Okay just so I am doing the math correct, 28,000 gallons is just a tick 3.6 million ounces. So i would add 10(3.6) or 36 ounces of 10%liquid chlorine? When I use the pool app from 0 to a goal of 4 FC it suggests 121 ounces. Where is my thinking off?

Thank You

 

[ajw22]

Trust PoolMath. 123 oz will raise your pool FC by 4 ppm.

 

[aeh0603]

1ppm = 1 mg/L = 1.3 ounces per 10,000 gallons
1.3 oz / % available chlorine = number ounces needed per 10,000 gallons of pool water to raise FC level by 1 ppm

since you are using 10% chlorine:
1.3 oz / 0.10 = 13.4 oz / 10,000 gal to raise FC by 1

since your pool is 28,000 gal:
13 oz / 10,000 gal = X oz / 28,000 gal to raise FC by 1
(13 oz / 10,000 gal) * 28,000 gal = 36 oz of 10% chlorine to raise FC by 1 (this is where you stopped in your math)

since you wanted to raise by 4 ppm:
36 oz * 4 = 144 oz to raise FC by 4 in a 28,000 gallon pool

Plugging the same numbers into PoolMath, it tells you to add 143oz of 10% chlorine to raise FC from 0 to 4 in 28,000 gallons.
A difference of 1oz in 28,000 gallons is negligible and probably just a difference in rounding somewhere.

PoolMath is much easier, use PoolMath

 

[pool4mykids]

Thank you for confirming. I am in process of changing out a substantial amount of the water. Temps here in Ohio are forecast for 45 F high the next seven days so it seems like a good time to do this. Then I will refill add salt and start the SLAM process to kill off any residual algae that may be residing.

Do you continue to run SWG during the slam process? I would assume so and use liquid chlorine to make up the difference for the slam chlorine level.

 

[ajw22]

Do you continue to run SWG during the slam process? I would assume so and use liquid chlorine to make up the difference for the slam chlorine level.

No, do not run the SWG during the SLAM Process. Add liquid chlorine. Using the SWG does not let you see the actual FC consumption and track where you are int he process.

Save adding the salt for after the SLAM is complete.

Add stabilizer to get CYA 30, lower your pH, and start the SLAM Process

 

[pool4mykids]

great. understood!

Process underway

 

[pool4mykids]

So far so good.
Have held FC at 10 for three days. Multiple brushing and vacuums. CC has registered zero two days in a row. Overnight drop test next. Hoping to add salt and start using SWG soon. Cold snap has hit and water is 55 degrees. I don't think the SWG will operate at that temperature. May have to keep up with the liquid chlorine but will still add the salt.