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lion22

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Hello to all. I'm a newbie and this is my first post. I want to start by saying this is an awesome website I ran across whilst trying to educate myself on proper water chemistry, due to my "raised eyebrows" regarding the Bioguard computer readings.

The thread "Bioguard = Run?" was quite the read. I'm blown away by waterbear & chem geek's comments in this thread. I guess I shouldn't be since the water chem industry is probably no different from any other industry making simple stuff appear difficult in hopes of selling you stuff you may/may not need, and/or could use inexpensive alternatives. CYA in the "ideal" range of 30-200 always seemed a bit squirrelly to me.

Now that I'm completely confused as to what is/isn't right/wrong, I would appreciate any advice you can provide to steer me in the direction of having the most "high quality", "cost effective" pool as is humanly possible. Presently, I regret owning a pool as it has become a bigger chore than dealing with teenagers, lol.

I have my latest readout and can provide whatever info needed for the proper guidance. Pls tell me what to provide as I don't want to fill up space with a lot of stuff not needed. Thanks in advance for any advice, and thanks for all of the great reading in this forum and on this website in general.

Sincerely, L22

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One of the most important things to understand is the chlorine/CYA relationship. The active chlorine level that disinfects the pool, oxidizes bather waste, and prevents algae growth is proportional to the FC/CYA ratio. So if the CYA climbs due to use of stabilized chlorine (Trichlor and Dichlor), then you need to raise your FC proportionately or you risk getting algae growth if there are sufficient algae nutrients (phosphates and nitrates).

To prevent algae growth in a pool without a saltwater chlorine generator (SWG), you need a minimum FC of at least 7.5% of the CYA level. For an SWG pool, it's a minimum FC of at least 5% of the CYA level.

If you do not already have one, you should get the Taylor K-2006 test kit. You can then post your full range of water chemistry numbers and we can go from there.

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Thanks much chem geek. I will look into getting the kit you recommend. Until I can order it/get it here, is it possible to use a computer reading I presently get from my local pool store? They use the Bioguard ALEX system which I think has the needed numbers. This is our 2nd year owning our pool and we have been getting those readouts weekly, sometimes twice a week, for the last 2 seasons. If the Taylor is more accurate I can wait, just wanted to get the ball rolling right away if I can. Thanks again, I REALLY do appreciate your time and knowledge.

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I'd wait. It's not just that the pool store systems are sometimes flaky, but they depend on operator competence and with part-time students working during the summer that can be iffy. You can get the Taylor K-2006 test kit at Amazon.

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All of them -- Free Chlorine (FC), Combined Chlorine (CC), pH, Total Alkalinity (TA), Calcium Hardness (CH), Cyanuric Acid (CYA).

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Here are my current numbers:

FC = 0

CC = .6

PH = 8

TA = 149

CH = 243

CYA = 128

Pool Info: 24k gal, IG vinyl, 1.5 HP Centurion pump, Sta-rite System 3 sand filter.

Other Info: Pool presently looks very clear, no visible algae. This is our 2nd season owning the pool. The CYA has NEVER been anywhere close to your recommended 30-50. This season, it's been as low as 92 back in July, and as high as 151 last Friday. The FC has NEVER been anywhere near your recommended 7.5% of the CYA (probably the problem, lol). I have not been able to get the FC off of zero since the end of last month. Our water here (in Minnesota) is very hard (we have a softener for our tap water). If you need more info pls let me know. Thanks in advance for your assistance; I'm am SO looking forward to handling this myself and getting away from being dependent on pool stores.

Lastly, while I am looking forward to buying non-pool store chemicals in the future, I do still have a small supply of Bioguard products I would like to not waste. If this is not possible, and would not be in my best interests, I will find a new home for what I have left. Thanks again.

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You have probably been using Trichlor tabs. You need to understand the following facts that are independent of concentration of product and of pool size:

For every 10 ppm Free Chlorine (FC) from Trichlor, it also increases Cyanuric Acid (CYA) by 6 ppm.

For every 10 ppm FC from Dichlor, it also increases CYA by 9 ppm.

For every 10 ppm FC from Cal-Hypo, it also increases Calcium Hardness (CH) by at least 7 ppm.

So if you had chlorine usage of 2 ppm FC per day and used Trichlor, your CYA would climb by 36 ppm per month. Even at half that rate, your CYA would still keep building up unless you had significant water dilution.

You should measure your fill water, though don't need to test it's CYA. It's the TA and CH that are most relevant for the fill water (perhaps the pH).

It's unusual for the pH to be high when using Trichlor so you have probably been using pH Up product and that raises the TA as well. You've been lucky to have clear water and not get algae. Are you using an algaecide or phosphate remover? Perhaps your fill water is low in phosphates.

So where to begin. Well, your CYA is high and the only way to reduce it is to dilute the water (or use reverse osmosis which is expensive). You can either lower that now or just try and maintain a higher FC level. However, since your FC is 0, you may already have some nascent algae growth using up the chlorine faster than the tabs can deliver it though usually the water would be at least dull if not cloudy. You'll need to switch to using chlorinating liquid or bleach which you'll need to add every day or two depending on how quickly your chlorine drops.

What exactly are the Bioguard products that you have? Some might still be useful or at least not harmful while others (like Trichlor tabs) you can save for use when you are away for a week on vacation.

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Spot on regarding the Tri tabs. I do now get the CYA/FC relationship; now I understand why the CYA has always been so darn high! As for pH, we never had to bring it up, only down using Bioguard Low/Slow. The TA we have never had to bring down, only up using Bioguard Balance Pak 100. It's been a ph/TA see-saw ride to say the least as mostly one or another (or both) are off our Bioguard "ideal" recs of 7.4-7.6 pH & Adjusted Total Alk of 125-150.

As for CYA, would it not be "best" to lower the CYA and get it to your 30-50 rec, understanding that will involve emptying/filling until it gets there? Would that target need to be a bit higher since the pool sits mostly in direct sunlight? You are spot on regarding the Tri tabs not keeping up as we use more than I remember using last season when things went smooth (or at least smooth to me before I started to get better educated). No problem not using the tabs. What is better, the chlorinating liquid or bleach, or perhaps it's what I can get cheapest since the one is double the concentration of the other?

One thing this season, just in case it matters. All seemed to be going smooth until the first part of July when we went away for a few days and NEGLECTED to check the Tri tabs and they of course ran out. We came home to a "first time ever" cloudy pool (the solar cover was on while we were gone), and we SLAM'ed and things cleared up in less than a week and the FC came back to what we thought was good (1-3). It did not hold for long though.

As for the water appearance itself, it is for sure not cloudy; however, slightly dull may fit the bill as I just looked at it again. Perhaps I'm comparing it to what I THINK is clear. There was also some visible algae growth not long after the aforementioned NEGLECT, that I think we got under control. I don't see any visible now.

As for Bio products on-hand we have the Low/Slo, Bal Pak 100, Smart Shock & Burnout 3, Back-up Algaecide, Natural Clarifer, Pool Magnet Plus, Scale Inhibitor, and of course the tabs. I think I'm now sick to my stomach after just listing all this junk, lol.

For info purposes, our normal routine is to test the water at the pool store weekly (more often when things go wrong), and then adjust as recommended by the computer readout. That was/is normally pH down with Low/Slow and/or Alk up with the Bal Pak 100. Weekly we would shock with the Smart shock (every 3rd week we'd use the Burnout 3 cause they said we could since it was cheaper), and add 5oz each of Back-up and Clarifer. We would keep tabs in the skimmers at their rec of 5 for our 24k gal pool size (2 in one skimmer, 3 in the other). Once a month we would add Scale Inhib. We would add 2oz of the Pool Mag Plus because of our hard water for every 1 hour of water we added to keep at proper skimmer water level.

I'm ready and willing to do whatever it takes, and to use whatever you recommend to use/not to use. Pls advise where to start/how to proceed and I will get the ball rolling. The Air Force in me is embracing the challenge of getting this as trouble/worry-free as possible, and getting gone the pool store dependence and/or multiple chemicals not in my best interests. Again, thanks so much for your time and assistance. I hope one day, when I gain further expertise and experience, I can pay it forward to someone else! Have a great weekend!

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OK, so you were keeping your TA high enough to have carbon dioxide raise the pH faster than the Trichlor lowered it. Because you will be switching to hypochlorite sources of chlorine (primarily), you'll need to lower the TA level, probably to around 80 ppm or perhaps slightly lower (say 70 ppm). Do you have any water aeration features such as waterfalls, spillovers, fountains, etc.? They tend to make the pH rise but you can use those to help accelerate the lowering of the TA through a combination of acid addition and aeration at low pH (around 7.0 to 7.2).

You can certainly lower the CYA, but if you don't want to replace that much water that quickly you can just keep the FC higher proportionally to the CYA level. 30 ppm may be too low if you are in a sunny area. 50 ppm is more typical, but 80 ppm should be the max because above that it takes too much chlorine to recover a pool if it gets algae. It won't get algae if you maintain the chlorine level, but mistakes do happen so you want your pool to be easier to manage if anything goes wrong. In your case, you've probably got low phosphates in your pool which is why it didn't go south before or the regular algaecide could have been keeping algae at bay.

You can use whatever is least expensive or lets you return/reuse the bottles or whatever is important for you (i.e. carrying less weight even if it's a little more expensive). You can use PoolMath to calculate dosages. Tabs in the skimmer could have caused some damage to your copper heat exchanger if you have one in a gas heater because Trichlor is very acidic and this builds up in the skimmer when the pump is off (it can also degrade the skimmer area and the plaster near it).

So here's the low-down on each of the BioGuard products, what they are, and what you can do with them:

Low/Slo -- this is dry acid and you can use that until you use it up. Using hypochlorite sources of chlorine will tend to have the pH rise so acid may be needed. After you use this up, switch to using Muriatic Acid. The reason is that Low/Slo is sodium bisulfate and builds up sulfates and higher levels can damage plaster.

Bal Pak 100 is "sodium hydrogen carbonate" which is a synonym for "sodium bicarbonate" which is identical to Arm & Hammer Baking Soda. You won't need that when using hypochlorite sources of chlorine because they are not net acidic

Smart Shock is Dichlor and copper (as copper citrate). For every 10 ppm FC added by Dichlor, it also increases CYA by 9 ppm. The copper is an algaecide, but can stain pool surfaces and cause blonde hair to turn greenish. Hopefully you didn't build up too much copper in the pool or you can risk metal staining if the pH rises. Your dilution of water to lower the CYA level will also dilute the copper. I would not keep this product. Though the Dichlor could be used if you needed to increase CYA, the copper isn't good to add.

Burnout 3 is 58% Cal-Hypo where for every 10 ppm FC it also increases Calcium Hardness (CH) by at least 7 ppm. You can use that as a source of chlorine when your CH is low.

Back-Up Algaecide is ADBAC which is a linear quat algaecide. While a reasonably effective algaecide against green and black algae growth, it can foam. If you ever use an algaecide (and normally you don't have to), I'd recommend Polyquat 60 since it lasts longer (doesn't break down as quickly from chlorine) and is non-foaming. You can keep this as insurance, but shouldn't need it if you maintain proper FC/CYA levels.

Natural Clarifier shouldn't be needed if you maintain the proper FC/CYA levels. Since you have a sand filter, it's possible you might need the clarifier if you have silt or clay get into the water, but for most anything else you won't need it. You can always add DE to the sand filter if you need better filtration for any reason.

Pool Magnet Plus is 36% HEDP and 1.8% phosphorous acid. The HEDP is a recommended algaecide so this is OK to use when you have metals in the water. You've got copper from your algaecide, but unless you are refilling with well water that has iron in it, you probably don't need this product. You can keep it in case you need a metal sequestrant, but if you need more there are other brands with more HEDP and possibly better pricing.

Scale Inhibitor is EDTA and 2-Butenedioic acid and shouldn't be needed since your CH isn't excessively high. You probably won't need this and EDTA breaks down from chlorine and there are other ways to manage high CH if that ever becomes necessary.

You can learn a lot more about how to maintain your pool by reading some stickies at the top of this forum and by reading the Pool School.

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Thanks so much chem geek. We have no water aeration features. I will digest the above info, run the Pool Math numbers, and will report back with the progress and/or any questions. As for the Tri in the skimmer, we have never had the pump off during the pool season. We were advised to run the pump 24/7, which I always thought was unnecessary. A few others I spoke with out here do the same so I just went with it. I was gonna get away from that this season, but then we had a few "problems" as described above so I left it alone. Is it necessary, or if not, what is a recommended amount of time to run it?

As for the Pool School link, thanks. I had already read through all of it (great info by the way!) a few times and have learned so much. I plan on going thru it again for further absorption. Lastly, regarding how to get the ball rolling, and without having yet run the Pool Math numbers which may answer this question---when I do run the numbers, does it give info as to what to do in what order and how long to wait in between? Thanks again.

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OK, the pump running the entire time would make the Trichlor more safe to use in the skimmer. Of course, it's expensive to run the pump that long and not necessary if you properly chlorinate. You shouldn't need more than one turnover per day so depending on your pump flow rate that might be only 4-8 hours per day.

PoolMath gives you amounts of chemicals to add to get to the target that you put in, but it doesn't give you those targets automatically. You look at the Pool School to find the targets appropriate for your pool. For example, plaster pools need to have calcium to protect plaster surfaces while vinyl pools do not.

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Thanks chem geek. I ran the PoolMath, and yesterday afternoon I added dry acid to lower pH, and last night I added liq chl (12.5%). Today, the pool has a slight green haze to it. I have not yet run the numbers, but will soon. Did I do something incorrect, or perhaps the green is due to a reaction to algae that may be there? The last of the Tri tabs are nearly dissolved in the skimmers and I don't want to add any more so I can start to use liq chl unless we leave on vacation. I'm kinda at a loss right now in not knowing how to proceed, and not wanting things to get worse.

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If it's a clear green then that could be copper that shows up more at higher pH. Though you added acid to lower the pH, the chlorine will raise it until it gets used/consumed. If your pH is higher than usual now, then if you lower it and the green fades then it's likely copper. In that case, you'll need to either keep the pH low or to use a metal sequestrant to bind to the copper. Longer term, when you do water dilution to lower the CYA level that will remove the copper as well.

If the water gets more cloudy green, then that could be algae but that seems unlikely not only because of the copper in the water and the ADBAC you previously used (though that won't last much more than a week), but also that I presume you are maintaining an FC level that is at least 7.5% of the CYA level.

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