Is this Mustard Algae ?

[CyclingCraig]

Water Test Results

FC: 5 ppm
CC: 0 ppm
pH: 7.3
Alk: 90 ppm
CH: 120 ppm
CYA: 45 ppm

Currently shocking at 20 - 24 ppm (I used 2 gallons of 12.5% chlorine and 3 bags of 73% Cal-Hypo)

Here is a picture of the bottom drain at the deep end (8.5 feet). I have circled an area of the stain portions of the liner. and also indicated two areas where there is no stain.

The stains are in portions of the shallow end as well (3.5 ft) and in the corners of the transition to the deep end ramp.

The stains don't scrub off with a brush, even with some force, but they seem to fade after shocking?

Does this look like a mustard algae bloom.:
[attachment=0:2pmgweyq]Stain.JPG[/attachment:2pmgweyq]

 

[Bama Rambler]

That just looks like staining. If it fades under high FC levels it's most likely organic staining and will fade if you hold the FC at the high side of normal.

 

[CyclingCraig]

Thanks for the reply

I did a test on the stain, Put a Tri-Chlor puck on the stain for 5 minutes. No change..

Then took some crushed up Vitamin C, put it in a sock, and in SECONDS.. Gone! I could almost just wipe it away.

So it looks like I will be doing the AA Treatment. But I have a Question. In the Instructions here it says:

"When the stain is gone, add enough sequestering agent for the volume of your pool - more is better than not enough."

For Jacks Magic "The Pink Stuff", there is an initial dosage rate and a maintenance dosage:
Initial: 1 quart per 10,000 gallons
Maintenance: 6-8 ounces per 10,000 gallons weekly

Which rate do I use? If the Initial, then for my 28,500 gallon pool, I'm going to need 3 bottles of that stuff, and at 20+ plus a bottle that is some cash!!!

Also, I am on city water, is it possible that the iron is coming from there, or I just had Patio block installed around the pool, and it's a good chance dirt got in the pool while they were digging around the pool?


Thanks
-Craig

 

[Bama Rambler]

Initially you need to use the "initial" dose and then the "maintenance" dose after that.

As you see, the initial and ongoing expense is one of the reasons we recommend refilling with known metal free water if you can. The cost of the sequestrant to provide the initial dosing is close to the cost of a complete water replacement in most places. The thing about the water replacement is then you don't have to keep up a level of sequestrant from now on.

Since you're on public water it's easy to check whether it has metals. All public water srevices are required to provide a water assay (report) to any user requesting one. Some even have websites where you can access the water report.

If you're on American Water you can go to http://www.amwater/njaw.com and get the report.