Small amounts of green algae

[Purplick]

I was just coming onto this site to post the same issue. I just opened my pool last year. I found your site and immediately used the TFP method. I had zero issues. This year the pool is a mess. I had a huge algae blow up in July. I did the SLAM and haven't been right since. I need to clean the pool every day. There is visible brown dirt daily. If I can't clean it every day, then the green starts. I passed the overnight chlorine test too. Since the SLAM I have not let the FC dip below 7. I can go days without a change in the FC number. Then I realized that I had a different issue. Not sure if this is causing everything but - My TA was high at 160, and PH was good at 7.6. So we added Muriatic acid to lower and I planned on aerating to raise the PH. Well, after I added the acid, here are my numbers:

FC: 7
CC: 0
PH: 7.2
TA: 150
CH: 140
CYA: 40
Salt: 0
Borate: 0

I don't know what to do from here. TA is still high. Or is this an acceptable number?? The water is cloudy and has been for a month. I can't get the algae under control.

 

[jeffchap]

Purplick, I don't think the TA or pH is your problem. It almost always turns out to be insufficient FC. How did you obtain the CYA reading and how confident of it are you?

 

[tim5055]

Welcome to TFP!

What test kit are you using to obtain the testing results?

 

[Purplick]

I used the test strips last year, but when my issues started in early July, I bought the Taylor K-2006. I would say if I am off on that number, it would be lower than 40, not higher.

 

[Purplick]

Purplick, I don't think the TA or pH is your problem. It almost always turns out to be insufficient FC. How did you obtain the CYA reading and how confident of it are you?

I think insufficient FC is how I ended up in the mess, but since mid/end of July, I've been literally testing daily. We were building a deck around the pool so it was neglected a bit. I rechecked everything tonight, and here is what changed:
FC: 5
PH: 7.3
TA:130

 

[jeffchap]

Bring your FC back up to 16 and keep it there as often as possible, no less than 3 times per day, and let's see what happens. Run your pump 24x7 too.

 

[Purplick]

So I've kept my FC at 16 or above since Wednesday, and this morning it was crystal clear again. Now I've gotten it clear before, but my problem was that in 2 days or so, it was turning green again. BUT - I think i figured it out. This morning I was planning on taking my stairs out of the pool, and scrubbing them down with bleach, just to make sure I had everything cleaned right and also its really hard to get the underside of the stairs when they are in the water. So as I was pulling them out, a bunch of nasty yellow/green water was pouring out of all the small holes. So basically, when I had my big blow up, the algae got INSIDE my steps. Which would explain why after I'd get it cleaned up, and drop the FC, the algae would pop back up again. It was all hiding in there, just waiting to grow. So i took the steps apart, soaked in a 50/50 beach solution, shook it all around and then rinsed. Hopefully this does it. I also put more bleach in tonight even though I was at 16 just to make sure. If this doesn't work, I give up.