Newbie SLAM help!

[ibesal]

I'm a recent pool store convert and trying to clear up my pool. It's green and cloudy. I adjusted my pH to 7.4 and my CYA is 30.
FC was 0.4 so i added 452 oz of 7.5% bleach to my 23,760 gallon pool based on the calculator.

I retested 2 hours later and FC was only 2. I added 390 oz of bleach.

Rechecked FC 2 hours later and FC is still only 2. Adding another 390 oz of bleach seems crazy. But I have no idea what is normal!

Pool is green and cloudy. No significant difference seen throughout the day.

Using Walmart brand bleach, less than 3 months old.

Help!

Sand filter. Vinyl liner.

 

[zea3]

What are you using to test your chlorine? When was the last time you tested the CYA?

 

[ibesal]

Walmart

What are you using to test your chlorine? When was the last time you tested the CYA?

Taylor K-2006. This morning.

 

[zea3]

How large is your pool? Can you walk me through how you are testing chlorine, just in case there is an error?

 

[ibesal]

How large is your pool? Can you walk me through how you are testing chlorine, just in case there is an error?

Pool is 23,760 gallons.
I'm adding a 10mL sample then adding 2 scoops of powder and swirling until pink and dissolved. Then counting drops and multiplying by 0.5. Is that what you're asking?
I just pulled another sample from a different part of the pool. CYA is still 30, FC is now 1.5 (3 drops to clear}.

 

[ibesal]

How large is your pool? Can you walk me through how you are testing chlorine, just in case there is an error?

A little further info... CYA had been crazy high last year before closing pool. So we uncovered pool and drained a significant amount of water and then left town for 10 days. Came home to a dead animal in the pool and green cloudy water. Filled the pool yesterday and started my first SLAM this morning.

 

[zea3]

Yes, so it sounds like testing is not an issue. Do you know if there are leaves or debris in the pool? A pool with a lot of debris will consume a lot of chlorine. It can take several days to slam the pool. If there is debris use a pool rake (deep net) and scoop out as much as you can.
OK, so the dead animal makes sense. Was the animal intact or had it ruptured? A ruptured decomposing animal will increase chlorine demand as well. Keep bringing the pool to slam level as often as you can, maybe check every 30 minutes or so if you are still seeing big drops in FC. Once the chlorine is holding a little better you can go back to checking every couple of hours.

 

[ibesal]

It was dark and I made hubby extract the animal so I'm not sure. He thought it had been there for a lot of our time away... Not very firm, I think.

We've been vacuuming the pool with robotic vacuum since yesterday morning. We were getting a fair amount of debris in the basket but I'm getting very little debris in the vacuum now. Some, but not much.

So when you say check every 30 minutes, do you mean to add more chlorine every 30 minutes (assuming FC is below 12)? Since this is new to me, I'm afraid of overdoing and ruining something.

Thanks for your help!

 

[ibesal]

Yes, so it sounds like testing is not an issue. Do you know if there are leaves or debris in the pool? A pool with a lot of debris will consume a lot of chlorine. It can take several days to slam the pool. If there is debris use a pool rake (deep net) and scoop out as much as you can.
OK, so the dead animal makes sense. Was the animal intact or had it ruptured? A ruptured decomposing animal will increase chlorine demand as well. Keep bringing the pool to slam level as often as you can, maybe check every 30 minutes or so if you are still seeing big drops in FC. Once the chlorine is holding a little better you can go back to checking every couple of hours.

So when I check every 30 minutes I should add more chlorine based on calculations? Adding many gallons a day won't damage anything if FC numbers are okay?

 

[zea3]

If you lose more than 1/2 your chlorine in 30 minutes then bump it back up to slam level. As long as you are at the correct slam level for your CYA you won't hurt anything.