Algae??? Not sure

[lawson23]

So twice this year I have had yellow on my liner mostly on the slope areas. The first time my chlorine was low and I just figured Algae but I also has some work done around the pool with digging and the other thought was that maybe clay fell in. This is the color that it looks like. So I scrubbed increased the chlorine and my chlorine was holding steady and CC went to zero.

I then just went away for 4 days this weekend and came back tested water and had really high chlorine in the 10 because I filled my triclor generator and turned it up a little so I would not have to worry. Then today, two days later after testing we removed the cover and bam yellow in different location but on the slope again. Is this actually possibly algae with the high chlorine levels?

I also tested again.
Results:
8/9/2021
FC 10.6
CC 0
PH 7.4

8/11/2021 (automatic chlorinator turned down back to normal)
FC 9
CC 0
PH 7.4
CYA 40

Thoughts?

 

[Texas Splash]

Did you ever really complete the SLAM Process though until its entirety? You needed to pass all 3 criteria. That is critical to remove algae.

 

[lawson23]

No I did not complete or do the SLAM process because the first time I was not 100% sure it was Algae just figured possibly.

I will add the water is perfectly clear.

 

[Texas Splash]

I will add the water is perfectly clear.

That's good to know. I would still run an Overnight Chlorine Loss Test just to be safe.

 

[wireform]

An OCLT is what needs to be done to actually see what you have in the water.

 

[lawson23]

Ok I will try to get this done today.
Yesterday I used the app to bump my FC up to 16. I did not test it though.
Now in middle of the day today I'm at:
FC: 13.5
CC: 0
I will do the OCLT tonight as long as my old axx memory doesn't fail me.

 

[lawson23]

ok just measured and added bleach
before adding:
FC: 12.5 10ml testing by the way
CC: 0

added 128oz of 10% bleach the app said 130oz.
The other thing I wanted to add it rained a lot while we were gone and of course every time it rains the spring tails are back.

Will try to test once sun is fully down and then in morning.

Will say losing a full 1 FC in 4 hours seems like something is up.

 

[wireform]

1 ppm loss during the day is actually very good as that's very little by uv standards.

 

[lawson23]

now test results:
Added some bleach earlier and tested FC to 18 at 11:23PM before I added the additional bleach I was showing a very small bit of CC but when I tested at 11:23 CC was back to 0.
Took another test at 7:11AM
FC 17.5
CC 0

 

[Texas Splash]

Seems to be holding well.

 

[lawson23]

Not putting any chlorine in yesterday and getting more rain last night my test results this morning are:
FC 12
CC 0
PH 7.6

Should I keep the FC up to SLAM level or do you think it is ok to start backing it down?

 

[Texas Splash]

Should I keep the FC up to SLAM level or do you think it is ok to start backing it down?

So it was 17.5 yesterday morning, and this morning it was 12. 5.5 of FC is a bit more than we like to see lost in a 24 hr period. I would maintain the SLAM today, look everything over really well, then do an Overnight Chlorine Loss Test starting this evening.

 

[lawson23]

FC 17.5
CC 0

 

[PoolStored]

FC 17.5
CC 0

Great. Hope you didn't add any chlorine after testing. Go to bed. Get up before sunrise and retest. Wishing you luck tomorrow!

Generally for OCLT, you should do your last dose 1/2 to 1 hour before sunset, keep pump running, then test after sundown and don't add anything else. Then get up before sunrise and test again. The difference is your overnight chlorine loss result.

 

[wireform]

Great. Hope you didn't add any chlorine after testing. Go to bed. Get up before sunrise and retest. Wishing you luck tomorrow!

Generally for OCLT, you should do your last dose 1/2 to 1 hour before sunset, keep pump running, then test after sundown and don't add anything else. Then get up before sunrise and test again. The difference is your overnight chlorine loss result.

Not sure where the sunset plays a role in OCLT. You can start the OCLT @9pm, just check and add if needed, then check 30 minutes later to know what you have. Then early am before the sun make sure pump runs 30 minutes prior to testing.

 

[lawson23]

So my biggest issue is it keeps raining here right now when I'm trying to do these test.
It rained all last night and this morning
FC: 14.5
CC: .5

So I have added enough bleach to go over 16 again and will test later.

 

[Texas Splash]

Hang in there! In between rain showers be sure to take care of all the other SLAM process tasks.

 

[lawson23]

Now FC 13.5
CC 0
Adding back up to shock level for the night and is raining of course again.

 

[PoolStored]

Now FC 13.5
CC 0
Adding back up to shock level for the night and is raining of course again.

Great, keep it up! You don't have to test CC again until pool is clear and you pass OCLT. Just do the CC in the morning after you pass OCLT. Save your reagents!!!

 

[lawson23]

So regarding everything I have been doing and going through I read about mustard algae. Do you think this is what I had/have? I ask because this says after slam to raise my chlorine way up for 24 hours.

Mustard Algae

Today We are going to show you how you can get rid of mustard algae in your pool. By following the steps in this guide and with no expensive chemicals.

www.troublefreepool.com

Chlorine/CYA Chart

EDIT: You will find a simplified and standardized version of this chart at Pool School, Chlorine / CYA Chart. Chlorine/CYA Chart by Chemgeek FC = Free Chlorine in parts-per-million (ppm) CYA = Cyanuric Acid in parts-per-million (ppm) CYA ........... Min FC3 ..... Target FC ...... Yel/Mstrd...

www.troublefreepool.com

Whatever it was it was yellow/orange color