Mustard Algae not going away?

[Maxomom]

Hello!

48 hours into a SLAM. Initially took pH to 7.4 with acid and mustard algae shock level according to pool calc. Then let FC drop to SLAM level and have maintained 16 FC based upon 40 CYA for 48 hours. Overnight test showed pool at 15 FC, 0 CC, and water is pretty darn clear. ( no direct sunlight as of this writing so will know for certain about clarity in an hour or so..) Sounds pretty good right? Should be done right? However after daily brushing and vacuuming I still have what looks like algae/mustard yellow stain on shady side of deep end. No amount of brushing is knocking this stuff off. Tried wire brush as well and no go. What do you think? Keep at FC 16 for another 24 hours, keep brushing and see what happens? I have never had this kind of staining except when I screwed up and got an algae bloom so I can't imagine what else could possibly stick to the side of my deep end this way. Thoughts?

Thanks!

 

[jblizzle]

If it is not brushing off, then it is not likely algae and must just be a stain of some kind.

Have you tried a vitamin C tablet or trichlor tablet directly on the stain for a few minutes to see if either lighten it?

 

[Maxomom]

Thanks for your reply.....and thanks for reminding me of these two little tests! Completely forgot about them...

My concern is that this area with the staining is exactly where I had an algae bloom (or so I thought??) so logic would dictate that it is algae yes? Haven't misidentified in the past... If you agree, I will go ahead and let FC do it's normal drop now and then I can get in there and test. If either C or trichlor lightens the stain, please remind me what to do next to eliminate the stains. I paid for a very thorough acid wash on this pool last year and I am not happy to have stains yet again...(

Thanks Jason....appreciated as always!

Paula

 

[duraleigh]

Algae, if it is somewhat recent, most always brushes right off. A stain that is not easily removed by a brush or physical contact is either not algae or is algae that has been there a VERY long time.

 

[nedchavez]

Also, just to clarify something:

If you did have mustard algae, the correct way to deal with it is to FIRST raise to SLAM level till you pass the three tests THEN raise FC to mustard level for additional 24 hours.

 

[Maxomom]

Thanks Ned and Duraleigh -

Perhaps I didn't read the SLAM instructions completely then. I don't recall seeing a reference to the order in which you take the pool to mustard algae shock level so I just decided to take it there first as this is what seemed logical. Could be I missed it.....?

Will get in there and further test the stain once the FC has dropped back to a level that is not so hard on the skin ) As I said, just had an acid wash less than a year ago so it couldn't be such an old stain...

Appreciate you guys...

 

[duraleigh]

If you have a stain that will not brush up and poof away easily, it is not mustard algae.

Your problem is a stain that you need to identify as either metal or organic but mustard algae is not the problem.