How can this be - issues with Chlorine???

[Wineutopia]

Hey Everyone - I was on vacation for 10 days last week and I added 2 3" tabs to the pool and brought to shock level with bleach. I returned and had a very slight issue with Algae - I started the slam process yesterday after these test results:

FC: 0
PH 7.2
TA 70
CYA 35

I added 250 oz of bleach yesterday at 10:54 AM.

This morning I checked the FC again and it was 0.5 so I added 98 oz of bleach again to bring up to an FC of 6. I just checked the FC levels again and they are down to 0.5 again - we have been getting a little rain today and some sun but nothing to make is go down that much. Any ideas??????? Thanks as always!!!!

 

[Shirker]

very slight issue with Algae

If you have anything living in there, it will drop your chlorine fast.

 

[Wineutopia]

We did get a lot of rain last week and the pool is about 2 inches higher than usual so it is very possible I have over 8600 gals in there now.

- - - Updated - - -

I just didn't think it would go through that much bleach that quickly. I have done SLAMs before and it never went through it that quick - The algae was very light - I swept one time so far and it appears to be holding it off.

 

[Jimrahbe]

W,

The main things that consume chlorine are... Sunlight and Algae...

The basic idea of a SLAM is to increase your FC to the SLAM level and hold it there... So after your first dose, test and dose again in a hour or so, over and over, until the FC starts to hold or at least slows way down on the amount it is decreasing.. Then you can start testing and dosing at greater intervals.

Thanks,

Jim R.

 

[Wineutopia]

Thanks Jim - I knew that about SLAM's - I just have never had one burn through that much bleach in such a short time. Thanks a lot guys,

 

[Richard320]

Here's something to chew on mentally.... what was your CYA before you left?

It's unlikely, but still possible, that your FC dipped to nothing and a certain soil bacteria got in the pool and converted CYA to ammonia. And ammonia will react with bleach and use it up about as fast as you can pour it in, until you've killed the bacteria with bleach and neutralized the ammonia. From then on, it's normal. So if you were at 50 or so and now you're down, there's your answer. If you were at 30-35, then it just sounds like you have a tough strain of algae.

 

[Wineutopia]

Thanks Richard - Yeah CYA was at 35 before I left for vacation - sounds like a "fun" strain of algae.

 

[JoeSelf]

Target 40 as your CYA level round up to tens place.

 

[zea3]

Did you test the CYA when you got back from vacation? If you had a lot of rain while you were away, it could have lowered some.

 

[Lilypad]

And just in case.....check the freshness of the bleach.