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

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Starlog for posterity re: swg cell performance in high phosphate water ;)

Continued flawless production of approx 1.5 ppm per day, approx 20%

FC 4.5
PH 7.4 (lowered 1x this week, but added jacks purple, which also lowered again)
TA 90
CH 90 (no purple flashpoint this time, but had added jacks)
CYA 70

Iron .2 or lower, hard to tell, slightly above shade of zero. Lowest its been.

Effects of jacks purple...mild iron stains on steps cleared immed. with one bottle (half startup dose). Will not add more til/if stains return.

Will test po4 next week for delta...also bought alum for future jar test out of curiosity and possible future treatment.
 
Getting ready to try an alum jar test. Going to use a 5 gallon bucket and assuming 12 lbs per 10,000 k gallon, will add half a teaspoon of alum until it flocs. Then well test po4 of filtered top water in glass jar and compare to raw po4 of pool.

Other weekly test:
Swg continues complaint free production. No cell problems despite high po4. Producing and consuming about 1.5ish per day...lower consumption rate than prior manual dosing. Water crystal clear and well behaved, so no nascent algae.

FC 4.5
CC 0
Ph 7.8 (adjusted after test to 7.5, only adjustment this week)
TA 100
Ch 100
Cya 65* will adjust...I do backwash and dilute via weekly top up.
Iron: .3 ppm before adding maintenance dose of Jacks.

Orthophosphate reading of regular water, diluted 1:1 with distilled water using Hanna Meter:
53,600 ppb - increase of 2600 ppb over 2 weeks

Concordance test: 50:1 dilution with distilled water in glass phials after cleansing with vinegar:
Taylor pool phosphate test (goes to 1,000) - pretty much exact color match on 1,000 x 50 for 50,000.
 
That is a very impressive amount of phosphates :shock: Glad to hear the SWG is working for you.

Pool use and temps have finally kicked in for me. I've been using a sonar bubble cover for the last few weeks having followed Mark's procedure for a DIY solar reel. Works great and I have to say using the cover has had a big impact on my chemical usage. I still only run my pump at 3 hrs/day with the output now at 45% on my SWG. I still haven't gotten down to my target FC level of 3.5-4ppm so now I am dialing in my SWG to lower output as opposed to decreasing pump run time. If I go below 3 hrs/day my water cleanliness suffers.

I've also run into another interesting discovery. There was always this problematic spot on my waterfall with a small rock that constantly had a little algae patch that would develop on the rock/mortar line (above the waterline but close enough to get splashed with pool water). It didn't matter what my pool water FC level was because its a consequence of poor waterfall design with inadequate flow of water and a rock plus mortar that always stays shaded and moist. The only way to deal with it was to use a spray bottle of bleach once every two to three weeks with a rub from a nylon brush to kill it all. It's a very, very small area so it never bothered me much, just life with a natural stone waterfall.

Welp, lo and behold, I have yet to see any algae in that area. This time last year I definitely had to treat it but so far, nothing. I'll keep watching it to see if/when it develops.

So far, the start of this swim season has been quite a bit different from years past....I'm not drawing any conclusions at this point, just keeping copious amounts of data. I will wait until the end of the summer to post my results and draw conclusions from it.
 
Lol. I'm not sure this crazy phosphate level is impressive to anyone other than hungry algae ;) Extra-ordinary, perhaps ;)
Speaking of which, interesting re: your waterfall, Matt.

So, I applied half a teaspoon of alum to a 5 gallon pail of pool water and left to to sit and flock for about 20 hours.

This morning I took "top" water in a glass jar, then filtered it through coffee filters into another glass jar. I then diluted the sample 1:1 with distilled water into the 10 ml glass cuvette just in case the level was too high to read.

My result was 6.6 x 2 for 13,200 ppb po4.

My pool po4 yesterday was 53,600 so the alum reduced phosphates by 40,400 in an application that simulated the mfg max of 12 pounds per 10,000 gallons.

I believe this means that 28 lbs of alum, flocced entirely to floor and vacuumed to waste, should remove in the neighborhood of 40,000 ppb. I am concerned about actually getting all the floc out as with the Seaklear it took me several days to completely remove same (slow well for refilling) and it was only partially flocced. Now that its hot, and I have an swg, I am concerned about maintaining an FC during such a treatment, as I don't want any of the alum running through the cell, heater, or filter. Manual mixing would disturb the floc.

So, we're going to decide about pulling the trigger on the liner when we get a final estimate on the observatory, whch as now changed location again. As such, I'll wait to decide on an alum floc, since no point if I'm trucking in water.

BUT for others, floccing to waste with alum should prove a cost effective annual method for controlling po4. In my case, Leslie's was charging 18 for 5 lbs, so it'd been half as much as the commercial po4 remover I'd tried.

Alum floc, notwithstanding the added sulphates, has the benefit of dropping out some metal, eg iron, as well.
 
Nice experiment with the floc. Did you adjust the chemistry prior to floc'ing? Did you see a noticeable "floc layer" on the bottom of the jar?

The primary problem with floc as a general purpose treatment is that it has requirements that are not generally applicable. First off, you absolutely have to have the ability to vacuum to waste with a floc as vacuuming up the "floc'ed" waste water at the bottom of the pool and pushing it through a filter would be a disaster in terms of filter loading. For cartridge and DE filters, loading would require tearing down the filter and cleaning it out which would be costly in time and, for DE, money.

Another problem would be isolating a main drain. I, sadly, have a pool with the MD tied in series to the skimmer (a lousy arrangement). When you floc, it is necessary to circulate the water for about 2 hours and then leave the water still for 8 hours or so until the floc settles to the bottom. Without a way to isolate the MD, vacuuming to waste with the MD active will cause some degree to mixing/turbulence in the water which will unsettle the floc'ed layer possibly leading to a re-clouding the pool.

Finally there are the chemical adjustments that a required. They are not burdensome, but you do have to make sure your pH, TA and CH are optimally set to ensure that floc'ing will work. Alum floc's have a tendency to drop the pH of pool water, so increasing it initially is very important, especially if there is a heater in the plumbing loop.

They way to think about floc's and clarifiers is this - floc's are fast and really drop the particulate load in water BUT they take a lot of elbow grease to make them work right and to clean up. Clarifiers are slower and force the filter to do all the work but tend to only be useful at adding that "final polish" to the water. Neither of them are bad to use per se but they don't generally add much value to pool water maintenance. Finally, if you search the TFP threads you'll find A LOT of posts by pool owners that tried floc'ing their pools with either no results at all or a clouded pool where the floc would just not settle to the bottom.

Lanthanum chloride, on the other hand, seems to "work" for the vast majority of pools without needing much specialized equipment. I think the general experience of those that have used it is simply the generation of clouded water from the lanthanum carbonate and lanthanum phosphate precipitates and the ensuing clean up required. In my case, and many other cases, it's simply waiting a short period of time for the filter to do its things. For those with sand filters, a little extra elbow grease is needed in the form of an added clarifier OR added DE to the filter. Of course, in your case, we went completely "off the reservation" in terms of phosphate levels and amount of product added at one time, so the learning experience alone was worth A LOT!!

If you do floc the pool, it would be nice to see what kind of effect it has on metal levels....perhaps an experiment you can try just before the new liner is installed and before you dump that pool water ;)
 
I might just live with the faded hopper until next year and try it ;) I have about six 100 yr old trees in locations that are due for pruning this year too so lots of competing expenses this year ;)

In my case, I am able to isolate the main drain, and i do have the recirculate option.
 
Interesting experiment. I'm curious about what kind of other results you are going to end up with. I'm glad to see it working in removing phosphate in an experiment like that.

If you do end up flocking with alum, plan on letting the water settle again after the first vacuum. I've had to do it 3 or 4 times to get it all out and actually get the results I was looking for. Since that takes a few days, it's a good idea to do when your chlorine is high. I was at shock level at CYA of 80, so there was plenty there for me to get through the couple days or took to clean it out.

BTW, how did your CYA drop from 90 to 65 in a week? That seems strange to me.

Sent from my SM-G920V using Tapatalk
 
Swampwoman said:
I might just live with the faded hopper until next year and try it ;) I have about six 100 yr old trees in locations that are due for pruning this year too so lots of competing expenses this year ;)

In my case, I am able to isolate the main drain, and i do have the recirculate option.
Click to expand...

I feel your pain on the tree pruning front - I have a row if 9 mulberry trees lining my front by the road way. They had never been taken care of by the previous homeowners nor any the big the mesquite trees in my yard. The mulberry's were over run with dead branches and has no form; they just looked ugly and dropped tons of leaves every fall. Between those and the overgrown mesquite trees, I finally bit the bullet last year and paid for a professional arborist to come deal with....I could have bought a top-of-the-line Dolphin pool robot for what it cost me in tree remediation :(
 
Treatment Nerd: my cya was 70...if I wrote 90 somewhere it was an ipadian bobo ;) With heavy debris load, I backwash weekly and had added the cya in April. With water temp at 88, cya drop was unsurprising to e considering all factors.

Btw, thanks for the alum tips. First, it was an awesome contibution in terms of cost efficacy for high load well dwellers like me. Secondly, my idea for the pre-removal test came from the jar test in the paper you linked us too, and I was impressed with the results. So even if I don't do it for the high load this season (eg dependent on liner change and new water) I am going to keep this trick in mind for annual control going forward provided I can gently control sulphate buildup in fresh water. My raw wellwater also as hydrogen sulphide -- remedied or at least controlled by the softener. But given the historic nature of this water, I'll be most comfortable using a bit of alum on a fresh water load, and incrementally/annually ;) in my case, while Seaklear is more convenient, the opportunity of trace iron removal is attractive enough to have me use alum instead.

Matt...you can imagine then the gleam in my new arborist's eyes today looking at the 100 year towering oaks ;) Probably a liner by the time I'm done ;) I might spool the project out over a few rotating years!
 

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STARLOG of PHOSpool:

SWG running strong despite several idiot power outages in area.

SWG running strong even when heater gets lo flo warning from recent inexplicable rise to 26 psi of sand filter.
(Suspect for some reason my cya addition via filter this time did not go well. Had to backwash before she blew.)

Swg not batting an eye at phosphate or riddiculous party peeps human load on Saturday night.

Yay swg.

Readings:
FC 8 (raised for party and it stayed there...now dialing down)
Cc 0
Ph 7.8 (nt yet adjusted this week.)
Ch 90. ... Still wanna know where it went
CYA 70...it raised 5 but seemed to increase filter pressure so I'll add next time

Test on Secondary Benefits of Alum Floc in Phosphate Removal

Tested 5 gal raw well water that read a shade over 2 ppm iron
Added 1/2 teaspoon to approx replicate 12 lbs per 10,000 gal

Ran out of iron test strips, ordered more, but posting pic of 24-hr visual results

Possible theory to confirm with test Tues: People who have high po4 due to HEDP sequestrants also have metals. If able to vacuum to waste and isolate drain, added benefit of iron reduction/removal makes alum floc both cost effective plus will lower future need for sequestrant, thereby reducing future po4 elevation levels.

Pic won post...wifi down due to power outage and AT&T can seem to handle upload. Will post a bit later.

image.jpg
 
You need one of those extra long curly straws so you can simulate vacuuming to waste...just don't swallow the floc-water, yuck!!

;)

Nice pic!! Looks like alum floc is an interesting candidate for possible metal removal. Maybe treatmentnerd can work out some practical limits for us.
 
I've been using the Leslie's Alum printed mfg instructions limiting to 12 lbs per 10,000 gallons in my simulations so that my results reflect real world practicality...assuming the mfg is printing practical levels ;)

But yes, very promising to my mind as a double benefit treatment for both phosphates and iron -- to keep both evils dwn to a dull roar each season, whether I have new water this year or not.

But I want to check ph levels and efficacy on sequestered water, etc. before i get tooooo excited. Btw, as I'm reading up, this is kinda the "European" way of metal management, where they don't sell sequestrant but typically oxidize and use alum to floc metals on startup or after large water additions.
 
Yeah, the Euro standards are very different. They operate pools on very low levels of chlorine and no CYA. They also use a lot of coagulation and flocculation techniques to remove particulates and metals. They also use carbon filtration for organics and DBPs. Chlorine, in small amounts, is injected into the return stream after all of their filtration methods. It's pretty complicated but it's a result of regulations that require FC levels to be less than 0.7ppm. I think their standards also only apply to public/commercial pools like US standards do or else there would be no way to operate a residential pool there.
 
STARLOG PHOSpool:

SWG...trouble free runner, producing as expected per guidelines

Water:
FC 5.5
Cc 0
Ph 7.6 (adjusted once, slightly)
TA 100
Ch 100 (refilled about 4" this week, evaporation, cooler weather and warm differential)
CYA 70 - did not take full addition as I had to backwash

PO4 52,800 - which is less than the 53,600 of my last test 2 wees ago. At 1:1 dilution this could be dilution accuracy issue, or somehow using jacks is now carrying out some of spent phosphate...which jacks tech had suggested would happen if I raised my ch. uncertain.

Iron...can barely read shade change at all, eg maybe .1 ppm max. However, not sure new Lamotte test strips are as accurate as previous tablet dissolving style (same kit but now instant.) had tablets left so retried test with same, no difference.

ALUM TEST PART THREE on sequestered pool water - 5 gal

1. Added 5 ml bleach for total reading f 40 ppm FC in order to attempt to break dwn sequestrant.

2. barely any change on iron reading, eh. Aybe shade from .1 to .15 ppm...this pretty much scuttles the test

3. Adjusted ph by 5 mg dry acd o reduce prev 7.6 to 7.0 a approx for floc efficacy

4. Added 1/2 tsp (2.5 mg) floc to replicate 12 lb o 10k g

HOPE: since my iron readings are not meaningful, this test is in part scuttled, but I am now testing in 1 day to see if phosphate removal is replicated and whether any sequestered iron releases per visual I'd in floc.
 
I'm gonna put this as a response to the thread title. The thread has gone a different direction but the question of phosphate remover still lingers. I hope I can drive another nail in the coffin with this.

My Son's wife is a bio-mechanical engineer from NC State. Her masters thesis essentially was about algae growth.

She is employed by a large int'l company that contracts with municipalities to advise them on how to manage their wastewater. So, essentially, she helps municipalities by advising them on how to manage algae that consumes the bacteria, etc in the wastewater.

I have to paraphrase but the conversation went like this...

Dave: Kathryn, you know about TFP. We are having a VERY animated discussion on Phosphate Removers. The idea is that algae can't grow in your pool if you remove their food....phosphates.

Kathryn: Well, they will just feed on nitrates. The algae species is up over 3,000 and they all have different characteristics but most of them can adopt a to a variety of food source and they really don't need much.

Dave: Well, my group believes that if you don't allow algae to live, having available food doesn't matter.

Kathryn: That certainly is the best assuming you kiil it....what do you use?

Dave: Chlorine

Kathryn; Yep, so do we. There is nothing better.

Dave: So if we adopt a methodology of constant chlorine that keeps algae out of a pool, phosphates become irrelevant, right?

Kathryn: Yep.

Dave: Then what do we do if, despite our methodology, we allow conditions that allow algae to grow?

Kathryn. Kill it with chlorine.

There was a bit more and the nature of her work involves a lot of other stuff but the takeaway I got was that simply keeping algae out of your pool is a workable and practical solution. As an aside, I was struck by what a believer she is of chlorine. She works in an industry that is VERY green and she believes, after 6 years of research, that chlorine is a incredibly effective control when dealing with algae,
 
duraleigh said:
I'm gonna put this as a response to the thread title. The thread has gone a different direction but the question of phosphate remover still lingers. I hope I can drive another nail in the coffin with this.

My Son's wife is a bio-mechanical engineer from NC State. Her masters thesis essentially was about algae growth.

She is employed by a large int'l company that contracts with municipalities to advise them on how to manage their wastewater. So, essentially, she helps municipalities by advising them on how to manage algae that consumes the bacteria, etc in the wastewater.

I have to paraphrase but the conversation went like this...

Dave: Kathryn, you know about TFP. We are having a VERY animated discussion on Phosphate Removers. The idea is that algae can't grow in your pool if you remove their food....phosphates.

Kathryn: Well, they will just feed on nitrates. The algae species is up over 3,000 and they all have different characteristics but most of them can adopt a to a variety of food source and they really don't need much.

Dave: Well, my group believes that if you don't allow algae to live, having available food doesn't matter.

Kathryn: That certainly is the best assuming you kiil it....what do you use?

Dave: Chlorine

Kathryn; Yep, so do we. There is nothing better.

Dave: So if we adopt a methodology of constant chlorine that keeps algae out of a pool, phosphates become irrelevant, right?

Kathryn: Yep.

Dave: Then what do we do if, despite our methodology, we allow conditions that allow algae to grow?

Kathryn. Kill it with chlorine.

There was a bit more and the nature of her work involves a lot of other stuff but the takeaway I got was that simply keeping algae out of your pool is a workable and practical solution. As an aside, I was struck by what a believer she is of chlorine. She works in an industry that is VERY green and she believes, after 6 years of research, that chlorine is a incredibly effective control when dealing with algae,
Click to expand...

I'll agree with what you just posted, but what happens when chlorine drops too low or is nonexistant? Do you have a faster more aggressive algae bloom than if you didn't have nitrates, phosphates, etc in your pool water? If you really want the world to know how much you believe that phosphates and nitrates don't matter, dump a 25# bag of 20 20 20 liquid fertilizer in your pool and take a video of it to see. The proof is in the pudding so they say. That will add 12.8 ppm of N, 12.8 ppm of P, 12.8 ppm of K to your pool along with some micronutrients.
 

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