Phosphates.....are they worth removing??

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JoyfulNoise said:
swampwoman outlined some of the theoretical calculations that chem geek did for her in a long-ago post - Phosphates.....are they worth removing?? - Page 5

Basically you need a fairly high phosphate concentration for calcium phosphate scale to show up in your cell, something like 25ppm :shock: Now the reason why it finds itself as an issue in heaters is due to the temperature dependence and the fact that water heaters (and water boilers) have such high heats that calcium scaling of all kinds (phosphates and carbonates) becomes a very typical problem.
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Yea, that's what I meant when I said Capo4 scaling was near and dear to my livelihood. That's what keeps me up at night! :mrgreen: One thing anyway. Lots of time with French Creek...many hours I'll never get back.

I'll check the thread, but about the article? Is that what they are alluding to?

Edit:

Glancing the Chemgeek numbers, we should see a ton of SWG Po4 scaling. Those are very low thresholds unless I'm missing something.
 
Hi guys. Patrick, I understood Chemgeek to mean that while the calcium threshold in my particular pool is low, that since most people aren't running 25,000 ppb P04, it's generally uncommon.

I've given some thought to my own particularly high levels today when talking to the lead tech support guy over at Halosource/SeaKlear. In addition to my high diet of phosphonic metal sequestrant, plus not draining down due to water table and location and well water with metals, I also recovered that water from a "swamp" and had 20 wheelbarrows full of leaves that decomposed over the course of 2 years that we know of...

In other words, I had lots of phosphate opportunity ;)

Re: SeaKlear's advice for someone with my level of phosphates, clearing, and imminent salt water cell installation (in response to my questions) -- This was an actual callback from a very informed and clearly senior tech advisor.

Note: This advice is specific to SeaKlear, which is pure Lanthanum Chloride, at Commercial Strength, which removes 9,000 ppb per 32 oz. in 10,000 gallons. (The residential kind is more like 3,000.)

A) Water temperature does affect efficacy/reaction -- just like AA, cold water will mean it will take considerably longer to work, but a week should be fine
B) Best course (in my case) is to slug FULL calculated dose (not partials/plural or sequential) in front of return in deep end for distribution. He says it will work better this way than incrementally.
C) At 25,000 ppb, I can expect a coagulation/floc-ish behavior, and expect to have to vacuum a coating off the floor -- and vacuum to waste -- at some point in the process
D) At this level, not only am I to backwash frequently, but also to expect after first 24 hrs approx to have to possibly babysit the sand filter for pressure spikes
E) At this high level, extreme cloudiness is very likely, and is likely to last between 24-72 hours generally. 4 oz. natural clarifier per 10k gallons is recommended to aid in clearing
F) His personal opinion is that phosphates become potentially problematic for people over 500 ppb...but whether that's relating to background nutrient levels or scaling wasn't clear and I didn't think to ask for the distinction.

HAYWARD ON PO4 -- This was a response that customer service went out and got for me after an initial apparent misunderstanding of what my questions were really about. It does not give us a rule of thumb, but does present what would happen warranty-wise: if the cell works at a test and not in your pool, then you'd need to figure out your water ;)

- "We do not have a set phosphate level that would void your warranty if exceeded. What I do need to inform you of is operation issues with phosphates that high. At that level, if not treated regularly you would notice that the phosphates will deplenish your chlorine level very rapidly. At that level, most likely as rapidly as the system can produce it and you would see that you are not getting a chlorine reading. If this was to occur we would not immediately replace the cell. It would need to be taken to a cell testing station to verify that it is not generating chlorine."

This person made every effort to be helpful, but based on the italics, if one is being literal/technical, either was not given precise information about the actual relationship of PO4 to FC production via scaling -- and seemed instead to assume the pool store stance, which makes no sense. I would expect if I maintained a 7.5% ratio with an SWG (not that this is recommended) or even the lower SWG normal ration, provided my cell was adequately sized and pump ran enough, I would also not have algae despite high phosphates -- as long as there was no scale interfering with production.
 
Swampwoman,

I dosed my pool yesterday with SeaKlear. I am currently waiting until tomorrow to test again because they recommend 48 hour from addition to testing. I only added 8oz and did so by very slowly dripping it into my skimmer. The water clouded up in 30mins. I back-washed my DE filter prior to adding the SeaKlear and I went from a clean pressure of 12psi (normal) to 15psi in under an hour. By 5pm yesterday evening (~7 hours after dosing) my water was completely cleared up and back to normal clarity. I ran my filter pump for 24 hours and plan to run it again overnight tonight. As I said, I will retest my PO4 levels tomorrow at noon to see where I'm at.

FYI, I did not use any clarifier, my DE filter performed just fine.
 
According to Rhonda's moved post, (Question about Phosphates), Pentair said also that high phosphates will deplenish your chlorine. Hmmmm. Wonder if those assumptions are based on unbalanced FC/CYA pools. The guy from SeaKlear sounds believable. I am no chemist, just thinking out loud.

- - - Updated - - -

BTW, JFN, why did you choose SeaKlear over Orenda? I am too lazy to read back in the whole thread to see if you already explained that, and besides the Blackhawks are playing...
 
I chose SeaKlear because I could get it on Amazon in a 1-qt (32 fl. oz) bottle for ~$40. Orenda PR-10000 is only available in 1 gallon containers for over $100. A gallon is way too much considering that the 8oz I added yesterday is almost twice as much as what I really needed to add. If my PO4 levels are reduced to zero as I expect/hope, then I will likely not need to add anymore for at least another year (or more) as I have no significant inputs of PO4 (my fill water is less than 50ppb).

Both products are commercial-grade removers that are pure solutions of lanthanum chloride, no other additives. One quart of SeaKlear removes 9,000ppb phosphates in 10,000 gallons of pool water while one quart of the Orenda product will remove 10,000ppb per 10,000 gallons. So they are of comparable strength.
 
MarianParoo said:
I thought I remembered that one of the products contained a flocculant. Maybe I am mistaken or one of them may have multiple options?

Looking forward to tomorrow's results!
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PhosFree (Leslie's) has a clarifier in it as does Orenda's CV-600/700 product line. The CV-600/700 also contains enzymes as well. In all of those products, the concentration of lanthanum chloride is far, far lower.
 
SW, I completely understand your PO4 is very high, and I appreciate the level relating to CaPo4 even with your low CH. If anyone should have phosphate related problems, it should be you.

I'm still curious about the warnings of high Po4 levels absent of CH levels. Why do they say it's still somewhat theorhetical that phosphates are a problem for SWGs?
 

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MarianParoo said:
JFN, Matt. Your first backwash looks like it was an hour later. How often since then?
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I backwashed BEFORE adding phosphate remover. Then I added phosphate remover. I did not backwash after that nor will i backwash again until I see tomorrow's results. You don't want to backwash the product out before it has a chance to work. The initial reaction converts lanthanum chloride into lanthanum carbonate. Then the lanthanum carbonate slowly converts to lanthanum phosphate. If you backwash too soon after product application, you won't reduce any phosphates at all.

Once my PO4 levels drop, I will tear down my DE filter and completely clean it out. I was planning to do that anyway as part of my annual "gettin ready for summer" pool duties.
 
Still at 15psi. It won't go down until I either backwash or tear down the filter.

The nice part about having my oversized DE filter is that I can take a big pressure hit like that and still have very good flow.
 
I'm still curious about the warnings of high Po4 levels absent of CH levels. Why do they say it's still somewhat theorhetical that phosphates are a problem for SWGs?
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I've been pondering this too, Patrick, and have one of my half-baked theories bubbling away. I have a feeling that at mfgs what the "science guys" think in product dev and what the customer service people relate may be two different things.

Like us, I think the manufacturers are "trying to keep it simple" in a case where there really are too many variables to account for. Most folks gripe about (and often don't even use) simple test strips, let alone scary ole drop kits or Egads, a phosphate test that only goes up to 5,000. Explaining to a consumer what I'm about to attempt might divert a sale or two or three ;)

This is the picture that's sort of emerging for me:

1. Temperature variance, ph, and calcium levels all contribute to whether high phosphate levels will scale a cell, making it much more difficult to formulate an accurate level/condition combination that's adequately predictive. You saw chemgeek's formula. I'm inqusitive by nature that that math still gets away from me ;)

2. Po4 scaling is supposed to be difficult to detect vs ch scaling alone - homeowner not likely to detect visually so its easier to theorize on a "functioning/not functioning" scale.

3. Cell longevity is related to rate of use...a T15 cell is rated equivalent of 500 lb of chlorine. Run time affects output. Good cell life makes for happy customers.

4. In my experience, extremely high phosphate levels do not equal algae if the FC : cya ratio is maintained, but to get the predicted lifespan out of a cell, nobody's recommending running at this ratio, plus industry guidelines don't acknowledge this ratio (though I've seen that starting to change.)

So 5. Someone with constantly high ph and ch and PO4 from anti stain and scale products is perhaps more likely to scale...but no swg mfg is going to tell someone not to use sequestrants...on the contrary, salt plus electrolysis/galvanization makes staining more likely ;) I'd asked the Seaklear rep about this, and his co. sells EDTA for this purpose and he would NOT recommend that I not sequester for these reasons :)

6. At the same time, some people try to reduce their pump times to save on energy. Telling a consumer to run their pump for 24 hours is again going to make for an unhappy consumer.

7. In reality, here at TFP, we assume a lower FC:cya ratio for swg because we're also assuming enough run time to keep the lower level constant instead of dropping by a few ppm the way manual dosing does. But that doesn't mean some short run and undersized cell users AREN'T dropping below recc levels for much of the day, depending on sun, when they run pump, etc. We tell them to dial it in, as we should. But swg folks not on TFP might find "dialing it in" a hassle, right?;)

8. Low FC levels plus high phosphates lead to algae conditions, which also make consumers unhappy with swg purchase decisions once a cell can't get ahead of nascent conditions...just like high cya puck users. A swg mfgs direct competition would be a convenience-focused puck user...;)

9. For these reasons combined, it would be easier to "train" people to simply treat to keep PO4 LOW enough that the lowest possible levels of FC still keeps the water clear -- from the mfgs perspective.

It keeps SWG looking simple, and dare I say it, Trouble Free. (Which it certainly can be in the right hands.)

Now WE know that true trouble free status comes from a deeper knowledge of variables/conditions, and the ability to accurately test the water as needed, and reduce unintended consequences by generally only adding known entities to the water.

But hey, commercially, that's a hard sell if your key feature is convenience and the product counter-positioned to you in the market is equally "convenient" -- and your competing product -- pucks -- are getting on the phosphate bandwagon to excuse an ineffective FC:CYA ratio ;)

SO with the myriad of pool water treatment products out there, rather than getting highly specified with consumers, rather than trying to sleuth out what all agents of action are in a pool the way WE often do (which I freely admit is very difficult and time consuming)...in terms of warranty guidelines instead of setting highly arbitrary PO4 levels, which would be conditional on not only ph, temp, ch, po4 but also in terms of production, cell size and run time practices... companies like Hayward are saying "Bring your cell to a testing center. If we can produce chlorine with it, talk to an expert to sort out your water conditions."

When I reason it out, I actually think I agree with their position ;)

And on the customer service front if a happy customer is a customer without algae, then telling them to maintain an arbitrary but unspecified "low" PO4 level may in fact help customers remain satisfied with their purchase decision because its helping their water stay clear despite lower-than-effective FC ;)

Do you have a headache yet? ;)

SO...the reason I've been very slow to change to SWG was because I am a different purchaser for them than perhaps the typical consumer. I accept the trade off of convenience in terms of hauling liquid chlorine to fiddling with the mechanics, thinking about my treatment protocol, actively controlling ph if necessary, recognizing that with metals, I'm best served first reducing metals in my source water, etc. to minimize sequestrant, etc. (which is why I doubled down on softener capacity before entertaining a switch...I now have both a soft water spigot plus a well water zpm plumbed for a drip irrigation system I'm putting in the terrace...no small expense in terms of set up, I might add, but one meant to last my years)

I'm also willing to spend a few hundred to attempt to clear or reduce my PO4 levels to increase the odds of swg being an effective treatment method for me, because its cheaper than trucking in new water or replacing a well ;)

For me, with my habit of buying refilled chlorine because I hate environmentally using so many plastic bottles, in terms of cost, even two years of cell life is a wash financially, so I'll run it as high and hard as I need to to keep my sparkly water.
With all of that, if I find swg isn't a fit for me, I'm not too worried because I know what to do ;)

So, the techs come out April 18 to open for me, and I've ordered 2 gallons of Seaklear commercial.

If Matt clouded after 8 oz and 30 min., my experiment may be hilarious in scope ;) I promise to take pictures!

If all goes well, the cell itself will be installed April 25th, with electrician coming sometime thereafter. On the 25th we're doing a one-time sand change because its too hard to move filter outside of the pool house for a deep clean and it hasn't been cleaned since the swamp recovery four years ago. I also expect it may be full of phos-goo by then ;)
 
UPDATE

Measured phosphate levels using two different tests.

K-1106 : 50ppb < [PO4] < 125ppb

Hach : 0ppb < [PO4] < 200ppb

In the case of the K-1106 the color of the test solution color was closer to 50ppb than 125ppb and in the case of the Hach test the solution color was a lot closer to 0ppb.

So I'm calling my phosphate level as of now less than 100ppb. I was up at 1000ppb so I did clearly reduce them by a factor of 10.

I also spent the morning tearing down and cleaning out my DE for its annual "deep clean". I will detail that, with pictures, in a different post as I think it will be instructive to others. I have a QuadDE filter which is different than the typical grid-style DE filters.

And, my filter pressure is back down to slightly lower than 12psi (I really need to buy one of those fancy TFP pressure gauges).
 
SW, wowsa... :study:

Theoretical could mean anything from "we don't Know" to "we don't want you to know".

There are so many variables and I'm thinking that the pH is a variable that is also variable. (being a literacy specialist my wife would love me for that, which which is which.)

From what I've read knowone has ever defined the pH in the cell, and to complicate things even more it would vary with output. By how much is a bit of a guess as its all a bit theoretical. :D

I didnt have an option, a SWG was hear when we bought our house but I love the automation, it's uncomplicated with no probes or calibration to worry about. Simply set the timer, dial it in and it's done. And then there's the super chlorination effect of the cell.

If I had high phosphates I would reduce them for sure.

Edit: Wow, snowing, that's awesome, we still need sunscreen just to hang the washing out. I just bought our skis for next year, can't wait. :D
 
JoyfulNoise said:
So I'm calling my phosphate level as of now less than 100ppb. I was up at 1000ppb so I did clearly reduce them by a factor of 10.
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Ive always thought po4 had to be below 30ppb to prevent population growth. - we've been through this before so don't both commenting hear, but...

Is there any benifit to expand your experiment bejond FC/CYA ratios a little to include algae population growth/phosphate concentration? You have balanced pool water with a known PO4 of ~100ppb. Would it add anything to draw off say a 100 litres and check for growth over five days in the absence of any FC additions? Just a thought.

I think I know what the outcome would be. From there though, if you could remove the algae with a protein skimmer or an algae net you would have a body of water with very close to absolute zero phosphate concentration and much lower nitrates too. Phosphate removal via bio mass removal, wouldn't be nice if it were possible in a pool.
 
AUSpool said:
Ive always thought po4 had to be below 30ppb to prevent population growth. - we've been through this before so don't both commenting hear, but...

Is there any benifit to expand your experiment bejond FC/CYA ratios a little to include algae population growth/phosphate concentration? You have balanced pool water with a known PO4 of ~100ppb. Would it add anything to draw off say a 100 litres and check for growth over five days in the absence of any FC additions? Just a thought.
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A small scale experiment of this nature was already done, see this -

http://www.mcgrayel.com/files/Phosphate_Facts_and_Myths.pdf

Certainly not a definitive experiment and really lacking in some fundamental controls.

I'm not entirely sure what your proposal would demonstrate? Any bucket full of water will eventually turn green from algae.

Again, this is not an attempt to use PO4 removers as sanitizers or to study the microbiology of algae growth. It's a long range experiment to see if I can manage my pool water with a lower FC/CYA ratio in a trouble-free manner. So, at some level, the microscopic details don't matter as much. Even if my hypothesis is proven in my pool, the result is not definitive proof that EVERYONE can then adopt lower FC/CYA ratios and have algae-free pools. This is very much an issue of population statistics where lots of different pool types would have to be experimented with and then, from a large sample, some conclusion might be drawn. The ultimate purpose of my experiment, assuming it works, is to give folks who want to try it a protocol for doing that. That's really all there is to this.
 

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