Do I have algae?

[TO116]

Hey Guys,
We had a pretty good bit of wind/rain last Tuesday, and after work I noticed the pool had a good bit of debris and looked VERY slightly cloudy. I vacuumed the pool and it seemed fine, I actually did an OCLT that night and it passed. This weekend though I noticed a good bit of green in the seams and corners of the liner. I vacuumed/brushed again on Sunday and there was a lot of greenish "dust" kicked up while I was brushing.

Looks and sounds like algae to me, but here's my issue... 1. the pool is crystal clear, while vacuuming on Sunday I actually noticed about 6 ball bearings around my main drain (from my polaris I assume, since it seems to have stopped climbing walls recently). 2. From about 7pm Sunday to 4pm today, my FC dropped from 6ppm to 5ppm, so nothing is consuming very much chlorine. and 3. My FC has not dropped below 5ppm since about 7/1.

Here are my most recent test results:
FC 5
CC 0
pH 7.2
TA 110
CH 200
CYA 50

So, do I have algae? Could it just be dirt? Should I SLAM anyway? What do you guys think?

Thanks

 

[cubbieblue]

I'd slam to play it safe but Im conservative that way. I had a big pool party sunday and a bit of haziness today so went ahead and slammed. Been crystal clear all summer til now.
At 50 cya your minimum is 4 for fc. Your target is 6-8. It appears you're on the low side. I add bleach manually and suspect in my case, it may have dropped a little too low after party. ( we just dump a half gallon in at night after use and test in mornings) Not sure if algae can get going if you are below minimum, but at 5 there is not much room for error.
I'd also suggest that green "dust" doesnt sound like dust at all lol. But I've never had algae in my pool knock on wood. If something seems off, it probably is.
Good luck and let us know how it goes!

 

[Wobblerlorri]

You may be on the verge of an algae bloom. Does the green dust "poof" when you brush it and disperse into the water, or does it just move on the bottom? If it poofs and disappears that's algae and you need to SLAM.

SLAM Process
FC/CYA Levels

if it just moved from place to place and doesn't disperse into the water, it's dirt. Just vacuum it up.

 

[TO116]

I'd slam to play it safe but Im conservative that way. I had a big pool party sunday and a bit of haziness today so went ahead and slammed. Been crystal clear all summer til now.
At 50 cya your minimum is 4 for fc. Your target is 6-8. It appears you're on the low side. I add bleach manually and suspect in my case, it may have dropped a little too low after party. ( we just dump a half gallon in at night after use and test in mornings) Not sure if algae can get going if you are below minimum, but at 5 there is not much room for error.
I'd also suggest that green "dust" doesnt sound like dust at all lol. But I've never had algae in my pool knock on wood. If something seems off, it probably is.
Good luck and let us know how it goes!

Yeah I pretty much planned on slamming because like you said, something definitely seems off. Also, good call on the target FC range. Though I've seen the FC/CYA chart enough times, I've just been using the range that the Pool Math app gives, which is 4-8.

You may be on the verge of an algae bloom. Does the green dust "poof" when you brush it and disperse into the water, or does it just move on the bottom? If it poofs and disappears that's algae and you need to SLAM.

SLAM Process
FC/CYA Levels

if it just moved from place to place and doesn't disperse into the water, it's dirt. Just vacuum it up.

It definitely poofs and behaves like algae, I'll be getting set up for a SLAM. Hopefully its a short one since I seem to be passing all of the criteria before I even start.

Thanks guys.

 

[Learning]

You may be on the verge of an algae bloom. Does the green dust "poof" when you brush it and disperse into the water, or does it just move on the bottom? If it poofs and disappears that's algae and you need to SLAM.

SLAM Process
FC/CYA Levels

if it just moved from place to place and doesn't disperse into the water, it's dirt. Just vacuum it up.

Thank you for the “poof” criteria! I’m questioning an issue in my own pool and wondered how to distinguish between debris and algae.