at how many PPM can algae NOT grow?

[mikeginder]

Every year around this time, I seem to get a whisp of greenish , yellow on the shallow end bottom. My CHL reading right now is 15 and hasnt been below 8ppm this season and i did a drop test with NO DROP Pollen?

 

[tim5055]

How much FC you need to maintain is based on what your CYA level is. Plus, if you get a little growth going you may never eradicate it unless you complete a full SLAM. Have you performed a OCLT to see if you indeed have something living in the water?

 

[Bama Rambler]

Most likely pollen or dust. I think I'd aim one or two of those eight returns toward it if possible and let it keep the place clear.

 

[mikeginder]

How much FC you need to maintain is based on what your CYA level is. Plus, if you get a little growth going you may never eradicate it unless you complete a full SLAM. Have you performed a OCLT to see if you indeed have something living in the water?

i did the OCLT, no drop overnight

 

[YippeeSkippy]

Are you brushing your pool weekly? Its one of the easiest things to forget to do, but it helps enormously.

 

[tim5055]

i did the OCLT, no drop overnight

well, then if you stay above the minimum on the FC/CYA curt algae is not going to start. Vacuuming or having a cleaner (I have an M5 robot) will keep the dust/ dirt in check. I am amazed how much blows into my pool each week.