First time spring opening

[linen]

I bowed to domestic pressure and used some 40% algaecide to precipitate the dead algae.

Which algaecide did you use? The only one that we recommend is:

Polyquat
Poly[oxyethylene(dimethyliminio)ethylene(dimethyliminio)ethylene dichloride]

The only algaecide we recommend using. Often sold in a 60% concentration as Algaecide 60 or something similar. Other kinds of algaecide have various problems, adding metals, foaming, bad smells, etc, depending on what they contain. Algaecide is most effective at preventing algae from getting started, and doesn't do very well against an active algae bloom.

I do not believe algaecides actually precipitate out dead algae.

Also, algaecides can help prevent getting an algae bloom, but they do not help (can actually hurt) the process of killing them.

@Smykowski...worbry's name has been added to the super secret list

 

[WorBry]

I had a feeling I would be reprimanded for my misdemeanour.

The 'algaecide' (hate that term) was a 40% polyquat; I made sure of that and wouldn't have used any other type.

http://www.poollife.com/index.php?optio ... &Itemid=57

Don't misunderstand me, I'm not at all knocking the 'sustained-shock' BBB approach. The pool was steadily clearing (down to a moderate-light white haze after 5 days), but it wasn't going to happen overnight and there was pressure to get the pool up and sparkling for the weekend.

I did consider using the 'Clarifier' (the bright blue stuff- polyacrilamide ?) left over from a pool opening kit (HTH) that I mentioned had been given by the previous pool owner, but it was probably at least 2 years old and, and I had read that if not used properly they can make matters worse, - didn't want to take that risk.

I had used the same algaecide last season when I had a mid-summer green algal bloom. I remember it well. Shocked the pool, it turned white, but still hazy after 24 hours. Whats wrong? Water sample to the pool store for analysis. The diagnosis - algae (really, there's a test for that?). You'll need this - Zap-It. I know it's algae, but surely it's dead....it's turned white. Never mind, take our advice, or it will come back. So how much do I add? The whole bottle, yes all of it, shock again after two hours, keep the pump running overnight, back-wash in the morning and again the next day, vacuum and you are done. Next patient please. Well it worked - by the next morning the pool was clear with the dead algae settled on the bottom.

But within a week it came back - despite adding the prescribed weekly 'maintenance dose' of algaecide. Inadequately controlled chlorination maybe played a part (just had a puck in the skimmer), but the main locus seemed to be a bath mat (natural rubber as it turned out) I had put under the pool steps to protect the liner. The under-side was clear, but the surface of the mat inside the steps was heaving. Took the mat out and algae cleared up. Cleaned the mat, put it back and the algae came back within a day or two. Tried adding the weekly algaecide behind the steps, but same result. And so it went on - removing the mat at the end of the day, cleaning it and putting it back before people swam. Very tedious and by the end of the season the mat had all but dissolved. This year I've found an all vinyl bath mat and will see if that works out better. If not, I might try using suction cup feet under the steps to improve the circulation. Either way, I hope that my intent to take better control of the water chemistry will make a difference.

So, no, I don't really have much faith in the algaestatic, let alone algaecidal properties of these poly-quat products, at least at the concentrations used in domestic pools, and I think the notion that somehow increasing the concentrate from 15% to 60% changes the chemical from a mere inhibitor to a ferocious destroyer, mercilessly lysing algae cell walls and spilling their contents (as some articles and product promos portray) is, to say the least, exaggerated:

http://www.clubpiscine.ca/78-tips-and-a ... uctor.html

http://rob-dr-duck-coxworth.wrytestuff. ... 113446.htm

Quote: "Algaecides are chemicals that kill algae as opposed to sanitizers like chlorine that prevent algae and bacteria from getting a foothold in the first place".

Even the product I used, quote:

"A weekly dose of Zap-it will kill all algae present in the water and protect against any future growth."

Not my experience.

I do think however that they (at least the one I used) are quite effective for flocculating chlorine-killed algae, probably acting in much the same way as the other polymeric chelating agents used in the clarifying products - cross-linking/binding cells together until they floc.

Whether those products are more effective or rapid, I don't. But on this occasion again, after adding the 150ml of 40% poly-quat early evening (pool maintained at shock level), the filter pressure was up within a few hours. Back-washed at mid-night. By next morning the water was very clear, with lots of settled algae on the bottom. Back-washed again and dosed up the chlorine. Late afternoon after work, vacuumed and then ran for a few hours on bottom drain only. Had been a hot day and FC had dropped to around 5ppm (strip test) by this time. Dosed again to shock level and switched back to mixed skimmer/drain. Next morning there was just a little dead algae to vacuum. Let the FC fall to 5ppm again and have kept it there. Don't yet have the Taylor kit so couldn't do a proper overnight loss and combined chlorine test. On the strip test, pH (7.2) and alkalinity (80) look OK'ish. The CYA is just registering in the 35-50ppm range. Only used Ca-hypo for the first shock. But I should probably take a sample in for full testing.

I promise not to do it again. Now, am I still on probation, or do I have to wait for the Taylor kit?

Irony is the weekend has been a washout with no sun expected until Tuesday.

 

[Smykowski]

Those quotes above are backwards. General consensus here is that bleach kills algae and other organics (plenty of reading on this site as to how, if you're interested), while algaecides prevent them from growing in the first place. This is why most users here only use PolyQuat for closings and not during the swim season.

While it's unfortunate that you had the struggle, those products you put in the pool did what they are supposed do. Problem was, the pool store had no idea what guidance to give other than "Here, put this in the pool, it'll clear up."

 

[WorBry]

Those quotes above are backwards. General consensus here is that bleach kills algae and other organics (plenty of reading on this site as to how, if you're interested), while algaecides prevent them from growing in the first place. This is why most users here only use PolyQuat for closings and not during the swim season.

Quite agree, and being a Microbiologist (primarily clinical) I should probably educate myself more completely on the subject. One problem I have with the notion of using algaecides for prevention however is that in any microbial system where a growth retarding agent is introduced, or for that matter a 'cidal' agent at sub-lethal concentrations, there is the risk of selecting out populations with increased resistance not only to that agent but, depending on the mode of action, other agents as well. That's why the BBB approach of "hit it and hit it hard" is so valid.

Actually did a fair amount of public health and environmental water testing in the past. Shame I no longer have access to the testing facilities.

Remember one instance at a hospital in a hot country (that I wont name). The outdoor staff pool was neglected. They had the filter running but were adding little if any chlorine. Riddled not only with algae but Pseudomonas bacteria (not good for you). No-one would use it. Came that a pool side soiree was to be held for a local dignitary. So they bunged in a lorry load of hypochlorite - shocked to say the least - the chlorine was off the scale. Had a bunch of workers wading in the stuff to furiously clean up. Come the night it was sparkling for sure, except that the dignitary decided to take a dip and was near blinded. The site engineer was sacked.

While it's unfortunate that you had the struggle, those products you put in the pool did what they are supposed do. Problem was, the pool store had no idea what guidance to give other than "Here, put this in the pool, it'll clear up."

What can I say. They need to sell their products. And as a pool newbie it's difficult to resist the '35 years in the pool business' advice. Yes it did work, but I think the main lesson from that first episode was identify the cause and not just keep treating the symptoms. How like the life :lol:

 

[WorBry]

Pool store results:

FC: 3
pH: 7.2
TA: 80
TH: 100
CYA: 20

Total Hardness is quite low, right? I guess using up the 2Kg or so of Ca-hypo I have to hand is not going to make sufficient impact. Need to add CaCl2?

Got a couple of triclor pucks in a floater to help bump up the CYA.

Edit:Checked at another store:

FC: 3
pH: 7.4
TA: 90
TH: 100
CYA: out of reagent

They advised that I definitely need to add (something like 3Kg) CaCl2 to bring the TH up to 200.

Edit2:.......or do I?!! After reading around the subject TFP seems that the consensus is that calcium hardness is really not an issue for vinyl pools unless excessively high, and that a level of 100 ppm should be perfectly OK. Boy, nearly got 'pool stored' again.

 

[WorBry]

Received the K-1515-C reagents and the FC/CC tests work expected; thanks for the advice on that.

I've got the CYA up to 35 ppm mark and so am looking to maintain the FC at 3ppm. So far so good. Switched from domestic 6% bleach to 10.5% pool bleach for now as they have it on discount at Canadian tire.

Actually the Aqua-Check strip FC test does tally quite well with the FAS-DPD around the 3ppm mark, so I'll probably continue to use it for quick spot checks after dosing.

Just as a side note on the algaecide. I've read that when using poly-quat in conjunction with shock treatment it is actually normal to see a marked and quite rapid drop in FC with little or no change in CC. When I first saw that I wondered whether, in the process of disrupting (denaturing) the algae cell wall, the poly-quat merely exposes more active sites for oxidation by the chlorine, so it is depleted faster. The lack of marked change in CC in that case might be explained by the fact that the clumped (floculated) algae cells/debris fall out of suspension and settle to the lower levels of the pool quite quickly. I pondered also whether the EDTA might be converted to a more potent (chlorinated) intermediate but can find no reference to such a mechanism.

What I did learn on further reading however is that EDTA (the active quat moiety of polyquat) is directly and rapidly oxidized by chlorine, and is, in fact, widely used for de-chlorinating water sources and systems. It's also the active agent in 'pool shampoos' formulated to counter 'green hair'.

Makes me wonder how many pool owners who are regularly adding poly-quat algaecide to their pools as a preventative measure are not aware that it is depleting the agent that plays a far more critical role in keeping their pools algae-free, and, if they are actually monitoring and maintaining the chlorine levels, are probably using more chlorine than they need to be.

I wonder also if the pool industry are aware of that. If I was not me I'd say 'probably'

With that knowledge, I definitely won't be using poly-quat algaecide as a preventative treatment again. It also makes me a bit dubious about the value of using algaecide at pool closing; I really can't see it lasting all that long, especially if the pool has been shocked as a double measure.

 

[frogabog]

I've got the CYA up to 35 ppm mark and so am looking to maintain the FC at 3ppm. So far so good. Switched from domestic 6% bleach to 10.5% pool bleach for now as they have it on discount at Canadian tire.

Actually the Aqua-Check strip FC test does tally quite well with the FAS-DPD around the 3ppm mark, so I'll probably continue to use it for quick spot checks after dosing.

Sounds like you've got a good handle on things (and you know your "quats" quite well too!) but I wanted to point out that with using liquid chlorine you'll want to dose your pool to maximum for your CYA level (~7ppm) either at night or before sunrise, so that by the end of the day you won't fall below the minimum (3ppm). Maintaining 3ppm would actually mean that you'll have to test and add chlorine around 3-4 times a day, and that's not convenient at all. With pucks, you could maintain 3ppm as they slowly release chlorine at a fairly constant rate, but it doesn't work that way when you're manually adding chlorine.

The general rule is to add chlorine to maximum at night. And assuming all is well you'll be back at, or close to 3ppm the next night when you dose back to maximum again. Some pools will only lose 2ppm per day, others might lose closer to 4. But after a while you'll get to know how your pool behaves any given day, depending on weather or bather load, and you won't need to test before the nightly dosing every time.

 

[WorBry]

Ah, OK thanks for that advice. Actually, after a sun-set dosing, the 3ppm level has been holding quite well over-night so far, but we have been going through a cooler spell the last 5 days or so, and I'm sure things will change as it gets warmer. Plus, the pool hasn't been used much yet. Only put the steps back-in a couple of days back. So I'll definitely take your advice on that.

Boy this is sure a change from the 'bung-a-puck in the skimmer' tack that I took last season (and as most of the pool owning neighbors do), but I'm sure it will pay off.

Just got a full tub of tri-chlor pucks that I need to keep hidden from the wife. Maybe keep them in reserve for topping up the CYA, if needs be, and for days away.

 

[frogabog]

Trichlor is good for vacations. And disinfecting creek water while camping :~}

It has it's purposes and if kept dry will last a very long time.

 

[WorBry]

Trichlor is good for vacations. And disinfecting creek water while camping :~}

Surely not for actual consumption? I dunno, maybe stabilizer increases your sun-tolerance :lol:

 

[WorBry]

OK, I think I'm into stable BBB mode. For now I'm dosing (with the 10.5% pool bleach) once daily (mid-evening) up to FC 5.5 ppm. The pre-dose residual FC is typically around 3.5 ppm, so I'm losing maybe 2 ppm over the 24 hours, which I think is quite normal? Like Frogabog advised, I'll maybe need to dose to max 7ppm as it gets warmer; the nights are still fairly cool. The pump is now going off from 10pm (two hours after dosing), until 7.30am.

One thing I have noticed though is that entire the liner wall and steps are absolutely coated with tiny bubbles, almost like the water is carbonated. Wipe them off and they soon form again. Cant recall seeing that last year when I just had one trichlor puck in the skimmer. Even the kids have remarked on the 'fizzy' water and the coalesced bubbles rising up from the steps

The pH is up a tad but OK, I think - goes up to 7.8 or so after swimming, but always returns to around 7.5 - 7.6. The TA, TH and CYA are still around 90, 100 and 35 (had them checked again at the pool store on the weekend). No air trapped in the pump chamber or bubbles in the return. The water is crystal clear. No dead algae/crud on the bottom, no frothing or film on the surface; cant see there being residual poly-quat from several weeks before.

Not that I'm concerned, more intrigued. Is it out-gassed CO2 or maybe O2 from sunlight breakdown of the hypochlorite, or what? Is it normal when using bleach and maybe just that I'm running at a higher chlorine level than last year?

 

[WorBry]

You wonder sometimes if pool stores deserve the reputation for inaccurate testing, but get this one.

Got a new pot of Aqua-Check strips and to my surprise the CYA was not registering anything (i.e. <35ppm). Better check to be sure. Off to the nearest pool store - one of the franchise groups - normally they have an old guy doing the tests who I sort of trust - he does give you the actual results without asking. Previously, even told me not buy the drop test kits they sell as they are useless.

On this occasion it was a younger guy covering. Told him I just wanted to check the stabilizer level and hardness. Watched him closely. What does he do but the pH and chlorine only. Your pool water is perfect he tells me. I said I know the pH and chlorine, what about the stabilizer and hardness. They are perfect too. Really, OK, what were the values? What size is your pool? AGP, vinyl, round 18' x 54", about 30,000 liters. I can see him looking in the reference book and he pronounces the CYA is 40 and the hardness 220 - perfect. But you didn't do the tests. Plus the hardness was 100 pm just five days ago and I've added nothing. Anyhow, could you please "re-test"....just to be sure? No need, they are perfect. Is there a problem with your pool water - cloudy? No, crystal clear, just a bit fizzy. Do you back-wash? Uh, yes when I need to. Probably algae starting, should probably add some algaecide.

A sales supervisor comes over and I can see the young guy dumping the sample. They have some private exchange and Supervisor asks me why I want a retest when the results were 'good' and why do I want to know the values anyway. Because the tests I was interested in were not actually done. Supervisor reluctantly tells him to do the tests 'again'. Oh dear, the sample has gone. Sorry about that. So what is the problem with your pool? Same nonsensical patter leading to, you guessed it, 'you probably need algaecide' And, maybe I would be better using trichlor pucks, so then I wouldn't need to be concerned about stabilizer as they already contain it !! Is that deliberate or just plain ignorance?

I think I'd better invest in some of the other Taylor test reagents.

 

[Darcehole]

Hi, WorBry. I don't know if you've purchased a test kit, or agents yet, but I saw your post that the Taylor K-2006 in Canada cost over $100. I found a website www.poolsupplyworld.com/search.htm?sear ... 06&x=0&y=0 that sells it for $44.99, same kit! I am fortunate enough to live on the Can/US border, so I have a mail drop in the States that I have things delivered to. I had the kit in my hands within 2 days! I am just starting the BBB system as well, so good luck to you!

Darcy

 

[WorBry]

That's convenient for you - I watched a TV item the other about people such as yourself, some with their house literally right on the borderline - out the front door they are in US, out the back and they are in Canada. "Just nipping to the US Dear, back in 5 minutes".

Unfortunately I'm not in that position, and as far as I know, Apollo Piscines is the only supplier of Taylor kits here in Canada. Yes, I have already purchased FAS-DPD FC/CC reagents (equivalent to K-1515-C kit) from them.

Their current price for the complete K-2006 kit indeed is 123 $CAN, but it can actually work out cheaper if you purchase individual reagents (because they import those in bulk at discount) and fore-go things like the plastic case. I'm in the middle of working out what else I need and the costs just now.

The other good thing is that they are based not far from where I work.