Does this look like mustard algae?

[kaymaza]

Hey everyone so today I was getting ready to brush the bottom of my pool when I noticed this collection at the bottom. I thought it was just dirt but I'm also wondering if this could actually be mustard algae? I swept it towards the main drain and it suspended into the pool like it was dirt. I've been noticing that my FC levels have been slowly dropping. On 2/1 I recorded my FC as 7.5 ppm. 2/2 FC was 6.5 ppm. 2/3 was 6 ppm. 2/4 it was 5 ppm. Today I recorded FC as 4 ppm. CYA has been <30. What do you think guys think should I just treat it as mustard algae and perform the SLAM process? I've also included some GoPro footage of this that I've uploaded onto Youtube. Appreciate any help thanks everyone!

 

[kaymaza]

Here's another video that I took just now. There is a wind advisory here in the Las Vegas valley so I'm not sure if this could also just be dirt that has collected at the bottom.

 

[PoolStored]

Looks like dirt, I wouldn't overreact. With FC of 5 and CYA <30...dirt. Best course of action is to perform this test, Link --> Overnight Chlorine Loss Test

 

[kaymaza]

Looks like dirt, I wouldn't overreact. With FC of 5 and CYA <30...dirt. Best course of action is to perform this test, Link --> Overnight Chlorine Loss Test

Okay will do. I'll plan to perform OCLT. Thanks!

 

[PoolStored]

Okay will do. I'll plan to perform OCLT. Thanks!

Before = after sunset. After = before sunrise. oooooh those early mornings...

 

[JamesW]

Possibly mustard.

I would do a SLAM.

 

[kaymaza]

Before = after sunset. After = before sunrise. oooooh those early mornings...

Forgot to mention that I'm currently adding CYA. That shouldn't affect the results of the OCLT in any way correct?

 

[kaymaza]

OCLT performed. Yesterday evening FC was 4.5, CC 0. This morning FC was 3.5, CC 0. I'm right on the border. I guess right now I should just continue to observe?

 

[JamesW]

I would do a SLAM.

 

[kaymaza]

Alright so I performed another OCLT and yesterday evening after sunset FC was 15 CC 0. This morning before sunrise FC was 17.5 🤔 and CC 0. No visible algae present. The SLAM process took about 2 days. Not sure why my FC went up to 17.5 but nevertheless, does 2 days of SLAM sound okay as long as the all the criteria are met to discontinue the SLAM process?

 

[PoolStored]

Not sure why my FC went up to 17.5

Jandy Tru Clear Salt Chlorinating System
^^ Did you turn off your SWCG?

 

[kaymaza]

Jandy Tru Clear Salt Chlorinating System
^^ Did you turn off your SWCG?

Yup it's been off.

 

[PoolStored]

Yup it's been off.

Likely testing error. Do you have a speed stir? How "fast" do you squeeze off the drops? (HINT:you should squeeze evvvvvvver so slightly, let the drop form and drop off the tip on its own). Do you hold the bottle vertical?

 

[Newdude]

Was the pool well mixed for each test ?

 

[kaymaza]

Likely testing error. Do you have a speed stir? How "fast" do you squeeze off the drops? (HINT:you should squeeze evvvvvvver so slightly, let the drop form and drop off the tip on its own). Do you hold the bottle vertical?

I do have a speed stir bit I don't use it for the FAS/DPD chlorine test. I angle the bottle about -30 to -45 degrees and then apply the drop one at a time while tapping the test tube so that it can mix accordingly.

I agree I do think it's a testing error. I checked the chlorine levels again this evening and got an FC of 15.5 and a CC of 0. Yesterday evening I had an FC of 15 and CC of 0. 🤷‍♂️

 

[kaymaza]

Was the pool well mixed for each test ?

Yes it was. I've been running my pump 24/7 throughout the SLAM process.