Algae Bloom

[Stars26]

Results
FC 5
PH 7.5
CH 50
TA 80
CYA 30

I have been doing pretty good at keeping the pool at the indicated 5ppm level, I add chlorine late at nigh, pump runs from 6 am til 4pm, but I have algae growing for some reason I can't quite figure it out.

CYA level was 45 back in May, and I thought that number would not drop, but anyways.

I need to increase CH to 150 correct?.

I am going to start slamming but can you please give me an idea as to what could be the problem.
Filter is showing 10 psi used to be at around 20 psi, I have not cleaned it since it was clean back in October and not used until april. I do backwash once a week or 2 weeks and recharge.

Thanks for your help.

 

[Richard320]

First, your vinyl pool doesn't need Calcium. So don't worry about it being low.

Second, low filter pressure could be as simple as a bad gauge. Does it drop to zero with the pump off? Does it go up slowly before you backwash? How is the flow in the returns? You might have a clogged impeller or something which means you have insufficient circulation.

Third: where is the algae? Is the water otherwise clear? If it's just in a few patches, that points to poor circulation and/or insufficient brushing.

 

[Stars26]

It does drop to 0.
It does go up slowly after backwash, I just back washed it and is just below 10.
Flow in the returns seems fine but in the shallow end not as good as it was before.
It started in the deep end on the wall, but just the junctions since is 60 degrees, I hope you understand what I am saying. I slammed it and went away, but now it started again.
The water is crystal clear, not cloudy at all, you really have to pay attention to notice the algae.
I am gonna start running pump 12 hrs to see if it makes a difference, used to do it, and you are right, once I dropped running time to 10 hrs this started 3-4 weeks later.

Algae is in a few spots.

 

[Richard320]

You know you need to SLAM to get rid of it, and since it's not widespread, I suspect it will go quickly. It certainly sounds like a circulation problem. Do you vacuum up a lot of pine needles? They can slip through the pump strainer basket and clog the impeller. http://www.troublefreepool.com/threads/81126-DE-Filter-Pressure-Down-From-11-to-6-psi

 

[Stars26]

Pine needles indeed!!

I will SLAM and run pump for 12 hrs daily, but for now, will run 24 hrs until I am good.
Thanks

 

[Richard320]

Pine needles indeed!!

I will SLAM and run pump for 12 hrs daily, but for now, will run 24 hrs until I am good.
Thanks

So are we to take it that that was the low pressure problem and that it's all fixed now?

 

[Stars26]

yeah, thanks very much.