*SIGH* Looks Like I Have da' Mustard

[Tom.B]

"Cowardly, cowardly Custard... Can't cut the mustard!"

Well, it's time to divert my previous thread: http://www.poolforum.com/pf2/showthr...093#post117093 about water testing and talk about what now seems to be a Mustard Algae issue I think I have. Sadly, I think I have had it for a while, but just fought it with $$$$ throw at Leslie's Pool Supply and Rising Sun Pools here in the Greater Raleigh area.

You can check the link above for my last published test results where my phosphates (PO4?) was around 125, but just in the past few days, they have shot up to between the 250 and 500 ppm range. I have begun pulling the FC up to the SHOCK level and may go higher if needed. Currently the water is beginning to cloud up.

Here are the latest numbers.

FC - 14 (I added another gallon of 8% beach after this test)
CC - .5
PH - 7.4
TA - 80
CH - 350
CYA - 55-60
Phos - 250-500 (closer to the high range)

I have hesitated to put in the bottle of Natural Chemistry PHOS-free until I talked to you all. But I want to fight this thing since I will be spending ALL summer by the pool this year (the past five years we owned a boat and spent all weekends down at the coast) and don't want to let algae ruin it. But hey... whatever it takes.

What say ye'?
(Thanks for everything so far. You guys are awesome!)

Tom-

[PoolDoc]

1. If you have the Phos-Free, go ahead and put it in.

2. Retest phosphates in BOTH the pool AND your fill water. To manage phosphates in a pool, you need to figure out how they are entering.

3. Tell me your pool specs, so I can stick it in your signature -- it's easier to answer with that info in place. (Size, shape, surface, pump make/model, filter type/make/model, other equipment)

4. Run your pump 24/7 if you're not already doing so.

5. Don't buy more PhosFree. Orenda's PR-10000 is cheaper, on a ppm removed basis, though it clouds the pool. Kem-Tek's product is cheaper than Phos-Free, though not as cheap at the Orenda product, but doesn't cloud your pool. You'll have to find the Orenda product via Google, and you'll need to buy a clarifier to use with. I'll post links to Kem-Tek below. However, I'd get the testing done before deciding to buy more.

Kem-Tek 265-6 Pool and Spa Phosphate Remover, 1 Qt ($16.50 on May 12, 2014)
(1 quart will remove 2,000 ppm PO4 from 10,000 gallons.)
Natural Chemistry 5221 Phos Free Pool Cleaner, 3-Liter ($19.80 on May 12, 2014)
(3 liters will remove 1,800 ppm from 10,000 gallons.)


Clarifier (needed if you purchase Orenda PR-10000)

Kem-Tek Pool and Spa Ultra Clarifier
GLB Clear Blue

[Tom.B]

3. Tell me your pool specs, so I can stick it in your signature -- it's easier to answer with that info in place. (Size, shape, surface, pump make/model, filter type/make/model, other equipment)

I have wondered about this. I filled out the form when I joined and thought that maybe it was hidden to everyone but the mods. Since I don't have access to my own profile, I was just guessing. :-)

18x36 Rectangle IG 27,000 gal. Vinyl liner with a Hayward 250 sand filter and 1.5 hp pump

Now that you mention it, we just had 4" of rain. During that, I drained TOO MUCH water out (thinking it would rain another inch... it did not... So I was forced to, once again, fill the pool with what I calculate was around 500 gallons. It's dark now, so I will test me municipal water during the daylight tomorrow, but I'd bet that's it.

I set the pool to run 24/7 and just added the PHOS-free.

Thanks again!
Tom-

[Tom.B]

Oh... How many Kem-Tek's should I get? I suppose I should wait to see the results of the municipal water test. If PO4 is high, I guess I need to have a few bottles in reserve to use when I refill. Otherwise, maybe just one or two if it will REALLY lower it 1000ppm/qt./10,000g. Seems a bit lofty to me.

[PoolDoc]

Yeah, let's see where you are, and what you're putting into your pool, before you start ordering.

Regarding the forms, I don't have anyone to work on them right now, but that will change, hopefully next week.

[Watermom]

Thanks for the subscription!

[Tom.B]

Yeah, let's see where you are, and what you're putting into your pool, before you start ordering.

As suspected, municipal water has nearly 500 ppb of PO4. The PHOS-free appears to not have had any affect on the phosphate level over the last 24 hours. Currently, the FC level is 15 and the CYA is up to 60.

Recommendations?

[PoolDoc]

Actually, 500 ppb is not bad; the water here has over 2,000 ppb!

If you'd like, go ahead and pick one of the removers (Orenda PR-10000 or the Kem-Tek product), purchase it, and take the phosphates below 125 ppb. BUT, keep your chlorine up. Low phosphates weaken, but do not kill algae.

-- I assume you aren't using any products that would ADD phosphates, like stain removers, United Chemicals products, etc.? --

How's your pool looking, or more specifically, how is the mustard algae looking?

[Tom.B]

Good assumption... No other products being used. I also just ordered four quarts of the Kem-Tek to give it a whirl to lower my PO4. Looking forward to not spending $50 per bottle on the stuff at the pool store.

The pool looks fabulous currently. The water has cleared up quite a bit and is what I would consider crystal clear. The algae seems to still be there, but is less than before (unscientific). It still appears at the seams of the liner and on the steps, however, we are keeping it brushed every-other day or so. I just wen out and had to backwash the sand filter. The pressure had jumped and there was no visible output from the jets. When I did, the water was very green coming out of the waste hose. Normal?

I have also raised the FC level up to 19ppm as of the test just a few minutes ago. I finally got to Wally World and bought 12 gallons of their 8% Great Googly-Moogly Bleach. Unfortunately, someone beat me to the 20 Mule. Oh well, live to fight another day.

I actually have another question(s): What is the upper limit for chlorine with a vinyl liner? With a CYA of 55-60, I hesitate to run to the +SHOCK+ FC level to 30 as noted in Best Guess, much less 70ppm! Where should I raise it to and how long should I leave it there to kill off the algae?

[PoolDoc]

I just went out and had to backwash the sand filter. The pressure had jumped and there was no visible output from the jets. When I did, the water was very green coming out of the waste hose. Normal?

No, that's an indicator of algae. If you can, put a few tabs in the skimmer, which will raise the chlorine level in the filter, without raising it so much in the pool.

I actually have another question(s): What is the upper limit for chlorine with a vinyl liner? With a CYA of 55-60, I hesitate to run to the +SHOCK+ FC level to 30 as noted in Best Guess, much less 70ppm! Where should I raise it to and how long should I leave it there to kill off the algae?

Unfortunately, that's a question without a good answer. It varies from liner to liner, even within brands. I've been told that dark blue tends to be the color most susceptible to bleach-out, because of the pigments or dyes usually used.

Having a liner you're concerned about is an even better reason to try the phosphates. I probably should let you know I have entirely selfish reasons for wanting you to try phosphate removal: this is a perfect test case, for VALID use of phosphate removers:
=> You clearly have chlorine resistant algae -- the backwash is almost absolute confirmation of that.
=> You have a legit concern about 'mustard shock levels' of chlorine.
=> You're behaving predictably from our point of view and seem to testing reliably . . . so the 'data' we get from you is likely to be meaningful..

But . . . I really do hope it works. It would provide us a very useful additional tool with which to help people.