Could you please help me?

[Twinmommy]

I have a 13000 gallon concrete pool, started at very green 9 days ago (Saturday before last). Added 1 bag of yellow treat first day then about 12 2.5 gallon jugs from pool store of liquid chlorine but on Thursday (after 5 days) the pool was only a somewhat lighter green/gray wth hardly any visibility. Pool store tested my water and said my chlorine level was off the charts (was turning their red dye clear from bleach) and I should add a small bag of sodium bromide for a 10,000 gallon pool and not add any more chlorine but wait a few days. I waited until Saturday and added another 2.5 gallon jug of chlorine... pool did not look any better. Sunday added 3 2.5 gallon jugs against pool store advice (they again told me I had a chlorine lock and not to add any more chlorine). Pool store tested my chemicals and sold me muratic acid and wanted me to add shock but I declined. They told me more liquid chlorine would not solve my problem. Yesterday my levels were -

Fc 5
Tc 5
CH 200
CYA 30
Ph 8.2
Calcium hardness 200
TA 80

I put in half gallon of muratic acid and added 3 more 2.5 gallon jugs of chlorine today. Pool still no visibility and green. I'm cleaning the filter very often and brushing pool. Should I just keep adding chlorine? My young children have been waiting every day to see a blue pool and it's just not turning around! Thanks so much for any help.

 

[BoDarville]

Welcome to TFP!

Pool store tested my water and said my chlorine level was off the charts...

The pool store will tell you that any FC reading greater than 5 ppm is "off the charts".

They told me more liquid chlorine would not solve my problem.

They are incorrect. In fact, the reason your not seeing the improvement you're expecting is because the FC for your pool (given a CYA of 30) needs to be maintained at 12 ppm constantly to clear up the algae (see The SLAM Process).

I would ignore any more advice from this pool store. The only chemical you need right now to clear your pool up is plain unscented liquid bleach.

Would also suggest familiarizing yourself with the Pool Calculator to assist in the proper dosage amounts.

 

[Twinmommy]

Thank you for your reply! I went to the pool calculater but am not clear about the FC ... should my target be 12? If so it says since I"m already at 5 I only need to add about one gallon of 10% chlorine... is that right? I've already bought many 2.5 jugs of liquid chlorine from pool store so am going to use that, but am not sure how much more I need to add. Sorry I'm not understanding but could someone make this more clear for me? Thanks!

 

[Charlie_R]

Pool store testing is notoriously inaccurate at best, especially the CYA test.

Strong suggestion is for you to get your own kit, the TF-100 being most popular here, or the K-2006. You can get either from http://tftestkits.net/ You will probably need the XL option, as you are about to SLAM your pool. Most kits that you can buy locally will only test to 5 ppm, and as noted by Bo, you need to be able to test at least twice that level. The kits I mentioned will do this.

By getting your own kit, you will know for certain what your pool chemical balance is.

If you input your pool gallons correctly at the top of the pool calculator -- 13000 instead of 13,000 -- you should be getting 113 oz of 10% (about 3 quarts 2 cups). Trust the number.

Now, how are you going to know how much to add, to keep it there? That is where the TF-100 comes in.

Go to that link that Bo gave you to the SLAM process, and read it several times. Things will start to become clear as to what you will need to do to clear your pool.

 

[BoDarville]

Twinmommy:

Since you are cleaning up a green pool, you need to follow The SLAM Process. The FC level is determined by the CYA level. Since your pool has a CYA level of 30 ppm, the target FC for the SLAM process is 12-13 ppm. Below is an excerpt of the Pool Calculator.

[attachment=0:14yry7kd]PoolCalcExcerpt.jpg[/attachment:14yry7kd]

If your current FC is 5 ppm, you would add 129 oz. of 10% bleach. The SLAM level FC is shown on the calculator as "Shock".

Keep following the SLAM process until you pass all of the following criteria:

1. CC is 0.5 or lower;[/*:m:14yry7kd]
2. You pass an OCLT (ie overnight FC loss test shows a loss of 1.0 ppm or less); Overnight FC Loss Test (OCLT)[/*:m:14yry7kd]
3. And the water is clear.[/*:m:14yry7kd]

After passing all of the above criteria, then you can lower the FC to the maintenance (goal) level of between 2 - 6 ppm.