Help with SLAM and Clearing water

[Lroberts32]

Since 4/27/16 we've been slamming the pool. Bought a Taylor test kit. Water has cleared very well but we're just not getting to 100% clear like we hope to be. Appx. putting in 5 gallons of 12.5% chlorine daily according to CYA chart. Backwashing nightly and brushing in morning and night when adding chlorine. Put DE in filter. Vac a few times but sediment just settles back in same spots on bottom of pool. Have had rain which added to water to pool but we did add a bit of well water too.

cya 75
FC 16.4
cc 0.1
tc 5
ph 7.2
alk 100
cal hard 240

Overnight test is losing bt 2-4 ppm FC. Decided to stop slamming and let the chlorine drop so we can start heating and swimming next week. Should we still be slamming instead? Seems like SO much chlorine.

Also, we do have phosphates which I'm told eat up the chlorine so is it possible the phosphates are eating chlorine at night and not organics. I mean how can algae be in there STILL?

 

[woodyp]

"Decided to stop slamming and let the chlorine drop so we can start heating and swimming next week." You have NOT passed the OCLT test. It takes what it takes.

There's your problem! That, and a sand filter is most likely to take longer to get it crystal clear. It is safe to swim up to SLAM level for your CYA. Carry on!

If you stop now, you lose all the investment in time, hard work and chlorine money only to start all over.

 

[Mr Bruce]

You would have been better off draining some of that water in the beginning, would have taken less chlorine. Especially in IL.

 

[treatmentnerd]

Based on the chart, shock level at CYA of 75 would be closer to 30. Pool School - Chlorine / CYA Chart

If you are running back and forth between 16 and 20 ppm of FC, you may simply not have enough chlorine in the pool to get the complete kill.

 

[pinguy]

You need to continue the SLAM at the proper FC level until you pass all 3 criteria.

1) Water is completely clear
2) OFCLT is passed
3) CC < .5

Don't worry about phosphates.