High Phosphates > 1,000 & High Nitrates 90ppm

I have a 26,000 gal pool with a salt generator. This is our 4th year and I suddenly can not keep chlorine in the pool. I have been using the BBB - putting in gallons of chlorine.

Latest test results:

Free Chlorine: .4 ppm
Total Chlorine: .8 ppm
Combined: .5 ppm
pH: 7.4
Hardness: 317
Alkalinity: 106
CYA: 58 ppm

PHOSPHATES: > 1,000
NITRATES: 90 PPM

I had a new sensor put in my salt generator, have boosted twice and am running at 70% and still can't keep chlorine!

So the recommendation is to drain the entire pool and re-fill with fresh water!

We are going away for a week, so I plan to add an algaecide, shock the heck out of it and run the system until we get back. Does this sound like the best approach?

Hi Apple;

Neither phosphates nor nitrates consume chlorine by themselves. They can promote algae . . . but without algae, they have ZERO effect on chlorine.

These things do:
+ Algae
+ Sunlight, in the absence of CYA
+ Sunlight -- even WITH CYA -- in the presence of sodium bromide (anything from United Chemical, various algae treatments fm others)
+ Yellow OUT, Mustard Master, and other ammonia based algae treatments
+ Bromine (tabs)
+ Ammonia from biodegradation of CYA (in spring or after a major algae bloom)
+ Urine, sweat, lotion from swimmers

Other things consume some chlorine, like most algaecides. But it's not a huge effect.

HOWEVER, it sounds like you are inferring chlorine loss from the fact that you've turned up your SWCG and have no chlorine. But, since you don't really know whether your SWCG is working properly, you don't actually know if there is chlorine in the pool to lose.

ALSO, your test numbers tell me you are getting results from some sort of digital reader, probably of test strips. These are typically quite inaccurate (even dealer models) and WILDLY unreliable.

SO, do this:

#1 - Get a cheap OTO / phenol red kit at Walmart and 12 gallons of *plain* 6% chlorine bleach.
#2 - This evening, within 2 hours of sunset, turn off your SWCG, add 6 gallons of bleach, and then test the water 1 hour after.
#3 - The following morning, within 2 hours of sunRISE, test again. If your results are DARK yellow, you probably have an SWCG problem, not a chlorine problem.
#4 - Test again that evening. If the chlorine has dropped a lot during the day, from the AM reading, you have low stabilizer AND a bogus testing process.

There are some other possibilities, so report your results here. Also, consider buy an K2006 or K2006C -- these are pretty much the cheapest reliable kits with a DPD-FAS chlorine test component.

Ben

Take a bucket of pool water and add chlorine to it. 1/4 teaspoon of 6% bleach in 2 gallons is 10 ppm FC. I'll bet you'll be able to have it register chlorine and hold it. If so, then you just haven't been adding enough to the pool and/or your chlorine generator may not be producing chlorine. You can take a water sample from the return when the SWCG is on to see if you register any chlorine.

It sounds like you've got nascent algae growth in the pool consuming the chlorine OR your SWCG isn't working.

Sorry I didn't get back to anyone - was having trouble logging on and then we were gone for a week. Happy to report that came home to a crystal clear pool - the chlorine level was very high 5.0!

Ok - I actually use both the OTO test kit and a K-2005 at home. The OTO shows plenty of chlorine but the k-2005 says it's low. (I will buy new kits today)

I took my water to two different pool companies. Yes, one used the digital test strips. The other used chemical drops. I am going to take water samples again today.

Both pool companies were telling me that it would be extremely difficult to maintain chlorine because of the phosphate and nitrate levels.

I will report back this afternoon.

Thank you

If you are going to be buying a new kit, why don't you get the one that we feel is the best which is the Taylor K-2006 or 2006C (same kit, larger bottle of some reagents). If you buy it through the Amazon link in my signature, the Pool Forum makes a little money on the sale which helps us keep this form online. Only buy if the seller is Amato Industries, however. Some other sellers are substituting the K-2005 which you do NOT want. Having this kit will make your pool maintenance much easier and you won't have to rely on pool stores for readings.

Quote:

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Originally Posted by applepar

Both pool companies were telling me that it would be extremely difficult to maintain chlorine because of the phosphate and nitrate levels.

---

And, lemme guess, they had something to sell you to fix that?

Please, please post your K2005 test results . . . and please consider purchasing a K1515 DPD-FAS add-on for your K2005. (link to PoolSolutions page with links to items on Amazon, in my sig below)

Meanwhile, keep your chlorine high.

(By the way, I deleted your other posts asking the same question. Please ask once, in one place. It makes forums really really messy when people start asking their question in multiple places.)

In the blue table, underneath the moderators and my posts, are a group of links. One says "Amazon Links for FAS-DPD Kits".

Ben -- you beat me to it. I was also getting ready to find the other posts and delete them.

I also forgot about the add on part of the kit.

Applepar --- don't buy a whole K-2006 or 2006C. Just buy the K1515 kit. You have all the other parts of the K-2006 in your K2005 kit. That will give you the component that you are missing, but do need.

Regarding signatures ---- at the bottom of my post (and Ben's above) are some blue links. Click on the Amazon link and you'll find the K-1515 kit.

Today's readings with the k-2005 kit:

FC=1 Ph = 7.4
TC = 2 Bromine = 1
CC= 1 Alkalinity = 100
CYA = 65

I feel like an idiot, but I don't see any blue links at the bottom of any replies.

Still don't see blue links, but found it thru Pool Solutions.

Not your fault; mine, with help from vBulletin.

You should see more, now, plus get notifications on posts you've made.