More dead with powder than liquid

[HeatherH]

Hello,
We have been SLAMing for two weeks. We had a thunderstorm that set us back a little, but we have seemed to have stalled a bit. The other night, we only lost 1ppm overnight and there was the tiniest amount of dust on the bottom (possibly pollen instead of algae, but I don’t know for sure). For the most part, we have been using 10% liquid chlorine this year. Last night, we threw in a bag of Cal hypo 56% (that or 53, can’t remember). There was a TON of dead algae this morning. This was the case last year also. Not matter how long we SLAMed, everytime we threw in the Cal Hypo, a bunch of dead stuff was there that wouldn’t be when we used liquid. Why could that be? It’s like liquid isn’t strong enough or something.

Our CYA is right around 40. We have been brushing daily and keeping the chlorine where it’s supposed to be. Should we just use the powder since it seems to be more effective? I just don’t get it. Pool is sparkling and beautiful otherwise. This is the EXACT same issue we had last year. Frustrated again!!!

 

[HermanTX]

For 17k gals -
1 gal of 10% LC will raise FC by 5.9
1 lbs of 53% Cal Hypo will raise FC by 3.7

So if your LC was old the % of active chlorine may be reduced which could be 1 possibility.
I am using
PoolMath Ap to do the calculations under Effects of Adding.

 

[Donldson]

Seeing stuff on the bottom is not indicative of anything working better. Most likely algae is clinging to undissolved cal-hypo and settling with it on the bottom, whereas with liquid chlorine it remains suspended and is filtered out instead.

 

[Bperry]

Hello,
We have been SLAMing for two weeks. We had a thunderstorm that set us back a little, but we have seemed to have stalled a bit. The other night, we only lost 1ppm overnight and there was the tiniest amount of dust on the bottom (possibly pollen instead of algae, but I don’t know for sure). For the most part, we have been using 10% liquid chlorine this year. Last night, we threw in a bag of Cal hypo 56% (that or 53, can’t remember). There was a TON of dead algae this morning. This was the case last year also. Not matter how long we SLAMed, everytime we threw in the Cal Hypo, a bunch of dead stuff was there that wouldn’t be when we used liquid. Why could that be? It’s like liquid isn’t strong enough or something.

Our CYA is right around 40. We have been brushing daily and keeping the chlorine where it’s supposed to be. Should we just use the powder since it seems to be more effective? I just don’t get it. Pool is sparkling and beautiful otherwise. This is the EXACT same issue we had last year. Frustrated again!!!

Are your poolmath logs up to date? Your FC level should be 16 or 20ppm depending on which of the CYA tests is accurate. If CYA is 50ppm then you have been below SLAM and if it’s 40ppm then you’ve been closer with FC at 16ppm. You might want to double check the CYA level once more and SLAM based on that.

 

[HeatherH]

My CYA is 40 and we are trying to stay right around 17ppm. We are testing consistently and I know the levels are going up with each type of chlorine. I’m not sure if the LC is old, but it doesn’t bring the FC up to where it should be when I add it. That’s really interesting about the algae “binding” to cal hypo! I didn’t know that.

We were down to .5 CC and then it popped back up to 1.5, so I’m not sure what’s going on. I suppose we will just keep at it…seemingly forever!

 

[Bperry]

My CYA is 40 and we are trying to stay right around 17ppm. We are testing consistently and I know the levels are going up with each type of chlorine. I’m not sure if the LC is old, but it doesn’t bring the FC up to where it should be when I add it. That’s really interesting about the algae “binding” to cal hypo! I didn’t know that.

We were down to .5 CC and then it popped back up to 1.5, so I’m not sure what’s going on. I suppose we will just keep at it…seemingly forever!

I hear ya. It’s just odd the logs showing 30CYA, then 50, then 30 again. I guess 40 is a good average if you haven’t added any more but I’d feel a bit better if it was more consistent. Make sure you test in the same kind of lighting each time.

 

[HeatherH]

Yea, there was one day where I got 50. Not sure what the heck I did there but when I retested it was 40. We have been vacuuming to waste so often that it’s been a bit up and down.