Who to believe - "byhand" or computerized water test?

[Henry_R]

The following are chemical facts that are independent of concentration of product or of pool size:

For every 10 ppm Free Chlorine (FC) added by Trichlor, it also increases Cyanuric Acid (CYA) by 6 ppm.
For every 10 ppm FC added by Dichlor, it also increases CYA by 9 ppm.
For every 10 ppm FC added by Cal-Hypo, it also increases Calcium Hardness (CH) by at least 7 ppm.

You are right that with your high CYA especially, and to a lesser extent with your somewhat high (though still manageable) CH, you need to dilute your water to lower these levels. As you can see from the above, even at a daily 1.5 ppm FC per day loss which is what you are seeing, that's an increase in CYA of over 25 ppm PER MONTH from Trichlor.

You need to check your county/state regulations since your HOA may fall under commercial/public pools and have very specific requirements for various chemical levels. If there is a maximum FC limit that is lower than I suggest, then you'll have to follow that limit and use alternative means to prevent algae growth, such as using Polyquat 60 weekly (at extra cost).

With your 100+ ppm CYA, if you maintain the FC level at around 10 ppm using chlorinating liquid or bleach so as not to raise the CYA nor CH levels, then you will prevent algae growth unless the CYA level is more like 200 ppm. With your high CYA level, a high FC level will not be harsh on swimsuits, skin or hair. 10 ppm FC with 100 ppm CYA is roughly equivalent in active chlorine level to a pool with only 0.1 ppm FC and no CYA. The only issue with the higher FC level is if people were to drink very large quantities of pool water on a regular basis (which obviously they shouldn't be doing anyway).

You should get your CYA level closer to 50 ppm. You should also consider using chlorinating liquid and getting an automatic dosing system such as a peristaltic pump or The Liquidator. If you want to continue to use Trichlor tabs, then you'll need to use a supplemental algaecide such as Polyquat 60 weekly or a phosphate remover or use 50 ppm Borates. Even so, the regs will probably require you to dilute the water to keep the CYA under 100 ppm.

In spite of these facts which I have relayed in turn to the HOA board members they are insisting that we NOT reduce the water level citing water costs. They do not seem to comprehend that the CYA will not go away like chlorine does.

They won't even pay for the TF100 kit which I feel will allow me to be more effective in keeping things under control. I put 2lbs and about 8oz of cal-hypo in yesterday (Sunday) morning based on the most recent chlorine levels and brushed the sides beforehand. I also put in some clarifier since there are visible particles in the water when I look at night that are just not being filtered out. By 3:30pm the water had really cleared up. But I cannot even measure the chlorine now to know whether it's correct or not. If I put enough in there it should be around 10ppm or so FC which is high-middle of the 8-13 FC range based on CYA=100.

For now the feeder is off. Unless it's valve leaks it should not be providing any chlorine. So the only chlorine added in the last week was last Sunday and yesterday. Both times I added around 2 lbs. If I could do that weekly for the rest of the summer it'd be fine actually. I still need the test kit so we don't have to rely on pool store people for the tests.

As for regulatory stuff. We are complying with local city of Houston codes that indicate we are a private pool, not either commercial nor public or semi-public. This has to do with the size of our community being 30 condos or less. They city doesn't even issue a permit for us and when requested to issue one we were told "no". So, unless we have a green pool which would be a violation of code, we're square.

State law seems to govern (semi)public pools and has little to say about private pools. And there is no CYA minimum or maximum as far as I can find in the commercial codes so that's OK too. FC is supposed to be 2ppm or more for state and local codes which is ok for us.

Our homeowners' cats sometimes drink the pool water for some reason. Otherwise I don't think we have too many people drinking it.

Thing is I've been told to keep out and we still don't have a pool service. Two relative novices who are my neighbors one being a board member (there are only three) have decided they know more about pools and to believe only those at Leslie's pools. I've tried to explain the chemistry stuff of CYA needing to be diluted by partial drain/refill and sent them both links to the pool school and such, but they both refuse to educate themselves about this. One of them was told the CYA would evaporate over time. ARG! And she believed it. There is no way I'm going to convince these two people to change to liquid chlorine if they won't even buy a test kit, but continue to rely on Leslie's for tests. I'm so frustrated with these idiots I can't think straight.

Sorry, I feel I'm ranting a little here...

I wish they would just hire someone, but even that seems to be failing because they don't want to spend the money. Does $350 a month including chemicals seem too high? I know this varies by market but is that outlandish or about average?

[chem geek]

CYA is like salt in the water. It will not evaporate.

It sounds like you need to just get out of this situation completely since they won't listen to you or educate themselves. As for maintenance cost, it varies by area but for Houston this link gives $275, this link in 2009 refers to service costing $120-160 per month, but you should call around to different pool services and see what they charge and what they do. That is, if you still want to be involved with this anymore.

If they don't want to dilute the water, then they should consider using an algaecide such as Polyquat 60 weekly to prevent algae growth unless they are willing to have the FC level be higher, at least until they do eventually get the water diluted (perhaps from eventual rain overflow?). Does the pool have a sand filter and get backwashed regularly? If so, that can help dilute the water somewhat, though not very much. As shown here, the water rate in Houston shows that even 20,000 gallons (pretty much a complete water replacement) at the highest marginal Multi-Family (TU 18 apartments 5+ units) rate of $3.53 + $5.13 per 1,000 gallons would be around $175 maximum so I don't understand the HOA concern about water replacement cost since it is more likely to be half this amount depending on how much you dilute.

By the way, if they were to do the weekly maintenance themselves, it would only cost around $40 per month in chemicals (chlorinating liquid or bleach), assuming 2 ppm FC per day chlorine usage. However, chlorine would need to be added to the pool regularly so automation such as The Liquidator would make that easier. Of course, the easiest would be a saltwater chlorine generator, but that's more expensive in initial cost. If you wanted to use Trichlor and maintain the CYA level at around 50 ppm using water dilution and assuming 2 ppm FC per day, then you'd need to replace almost 500 gallons every day! Even maintaining 100 ppm CYA and assuming 1.5 ppm FC per day you'd still need to replace over 180 gallons per day!

If you continue to use Cal-Hypo, then you will continue to raise the CH level, though it won't rise as fast proportionately as the CYA level would rise by using Trichlor. A higher CH level will eventually lead to scaling and the pool will remain cloudy longer after Cal-Hypo addition.

[Henry_R]

CYA is like salt in the water. It will not evaporate.

It sounds like you need to just get out of this situation completely since they won't listen to you or educate themselves. As for maintenance cost, it varies by area but for Houston this link gives $275, this link in 2009 refers to service costing $120-160 per month, but you should call around to different pool services and see what they charge and what they do. That is, if you still want to be involved with this anymore.

If they don't want to dilute the water, then they should consider using an algaecide such as Polyquat 60 weekly to prevent algae growth unless they are willing to have the FC level be higher, at least until they do eventually get the water diluted (perhaps from eventual rain overflow?). Does the pool have a sand filter and get backwashed regularly? If so, that can help dilute the water somewhat, though not very much. As shown here, the water rate in Houston shows that even 20,000 gallons (pretty much a complete water replacement) at the highest marginal Multi-Family (TU 18 apartments 5+ units) rate of $3.53 + $5.13 per 1,000 gallons would be around $175 maximum so I don't understand the HOA concern about water replacement cost since it is more likely to be half this amount depending on how much you dilute.

By the way, if they were to do the weekly maintenance themselves, it would only cost around $40 per month in chemicals (chlorinating liquid or bleach), assuming 2 ppm FC per day chlorine usage. However, chlorine would need to be added to the pool regularly so automation such as The Liquidator would make that easier. Of course, the easiest would be a saltwater chlorine generator, but that's more expensive in initial cost. If you wanted to use Trichlor and maintain the CYA level at around 50 ppm using water dilution and assuming 2 ppm FC per day, then you'd need to replace almost 500 gallons every day! Even maintaining 100 ppm CYA and assuming 1.5 ppm FC per day you'd still need to replace over 180 gallons per day!

If you continue to use Cal-Hypo, then you will continue to raise the CH level, though it won't rise as fast proportionately as the CYA level would rise by using Trichlor. A higher CH level will eventually lead to scaling and the pool will remain cloudy longer after Cal-Hypo addition.

I am going to try and stay out of it, but it's hard to watch a train wreck and not render aid.

Yeah, I know CYA will not evaporate. But the people who have taken control of the maintenance of the pool are so pigheaded that they won't listen. From everything I've read the only way to reduce it is to dulute.

I don't know if they're even looking for a pool service and I have no desire to do someone else's job anymore.
Our problem has been that no one calls back at this time of year. When we completed remodel of the pool last year we only had 5 companies who even showed up to bid or called back, out of 20 we called. That same thing is the issue we have now too; no return calls or standing us up. And the ones who do bid over bid and are hence unaffordable. They seem to see a condo association and think we have infinitly deep pockets. We have not budgeted for >$500 per month that we've been getting. The last one bid $350 + chemicals. Our HOA has other expenses and so the budget is tight.
These two things are preventing our finding a pool service to properly maintain this pool.

The water bill information is interesting. I was under the impression it was more than that to fill the pool. Last year we saw a $1000 rise in our water bill following the replaster when we filled it up. I attributed it to the refill of the pool but perhaps not. Problem is our overall water bill still runs $1500+ per month which comes out to $50 per unit. This is perceived as expensive when a private home would pay only $20 or so and so the Board are being tight about the water.

The chlorination is going to continue to be via cal-hypo 73% until someone tells these novices otherwise they won't listen to me anymore. I will not be able to explain the need to use liquid if I cannot even get them to buy a proper test kit. These people have no care to listen to my information since they've convinced themselves the people at Leslie's know best.

The tablet feeder if off and will remain off for now unless someone changes it or the valve is leaking(?).

As for a Liquidator or SWG, not a chance they'll spring for either one. Either would require us to rewire the service panel for capacity too. These are 40+ year old condos with 12 or 14ga aluminum wire mostly and Federal Pacific Electric (FPE) service panels. I think we have a double-pole 20A breaker for the pump, but it might be a 30A. The panels use Stab-lok connections and breakers are expensive. Also, these units were originally master-metered and the dim-bulbs who installed individual meters we have placed them butted together as many as four with no clearance between them. The panel for the pump is sandwiched between two other panels which would make it more expensive to upgrade.

[off topic]
Is it normal to have to routinely drain the pool due to high CYA? Do people normally have to do this when they use tablets? The reason I ask is in 18 years of living here I've never until now seen pool water level drained and then replaced. We've been using 3" trichlor since I began helping in 2009, but perhaps the chlorine was maintained some other way in the past? There was a tablet feeder installed so I ass-u-med that that was the way to go and probably had alway been but now I'm not so sure. The pool service we used when I first moved here in 1993 was a single individual who shocked the pool heavily once weekly. He'd been servicing the pool probably since the mid-70s or early 80s. In 2007 the management company we had at the time changed to another service when the man kept overfilling the pool and leaving the hose on plus his price went up.

In 2009 that service was let go for various things including leaving the gate unlatched in violation of city code and possibly using chemicals improperly. Under their tenure the plaster degraded rapidly and began to
fall off in chunks which is how we ended up having to replaster. Since June of last year following the replater the pool service we hired used 3" tablets and added them as needed as well as cal-hypo and perhaps some other non-chlorine based sanitizer too. We didn't begin to have any issues until March/April this year when people started using the pool. We have two algae blooms in three weeks time in April (After Easter for two weeks) and another over Memorial Day weekend. All of the incidents included the tablet feeder going empty and the pool man not getting ahead of it before it got out of hand. And in both cases when the pool man tested the water we had large excesses of phosphates >1000ppm. He used phosphate reducer, chlorine etc and it took days to bring it under control. He was fired during the last incident three weeks ago when he failed to return repeated urgent phone calls about the pool being green which began our servicing the pool ourselves. First thing we did was test the water. TC was near zero, CYA was >100 and phosphates were >1000ppm as I said at the beginning of this thread.

So why did the CYA jump up all of a sudden? If the tablet feeder is set too high for days would that perciptate high CYA? I know the man had the feeder set to a lower setting and had to turn it up some to keep chlorine levels normal. The notes the pool man was leaving indicated normal stabilizer in the 60-70ppm range so I'm trying to figure out what went wrong. Where did it get out of control that required draining to get it down?

Anyway, the reason I'm asking all this is that the Board members who have lived here as long as I have and having never seen the pool drained/refilled routinely they hence conclude it's unnecessary and refuse to allow it. Therefore if we use the feeder they're not going to understand the procedure necessary to keep CYA from rising too much. So they only way to chlorinate is going to be through cal-hypo of which we have about 40lbs left out of a 50# bucket. [/off topic]

[chem geek]

Is it normal to have to routinely drain the pool due to high CYA? Do people normally have to do this when they use tablets?
:
All of the incidents included the tablet feeder going empty and the pool man not getting ahead of it before it got out of hand. And in both cases when the pool man tested the water we had large excesses of phosphates >1000ppm. He used phosphate reducer, chlorine etc and it took days to bring it under control. He was fired during the last incident three weeks ago when he failed to return repeated urgent phone calls about the pool being green which began our servicing the pool ourselves. First thing we did was test the water. TC was near zero, CYA was >100 and phosphates were >1000ppm as I said at the beginning of this thread.

So why did the CYA jump up all of a sudden? If the tablet feeder is set too high for days would that perciptate high CYA? I know the man had the feeder set to a lower setting and had to turn it up some to keep chlorine levels normal. The notes the pool man was leaving indicated normal stabilizer in the 60-70ppm range so I'm trying to figure out what went wrong. Where did it get out of control that required draining to get it down?

As for the CYA level in pools, the answer depends on the specific environment for the pool. Water dilution can occur from summer or winter rains where the water overflows and gets auto-filled, for example. There is a slow breakdown of CYA by chlorine, though that's usually only a few ppm per month. If a pool is let go over the winter with the chlorine getting to zero, then bacteria can convert CYA into ammonia creating a huge chlorine demand upon opening though sometimes other bacteria convert the ammonia to nitrogen gas while algae use it for growth. So some people find that most or all of the CYA is gone when they open the pool in the spring. However, this is not a consistent effect. Also, some parts of the country have short swim seasons so there is less CYA buildup. Also, as the CYA level rises, the amount of chlorine loss from sunlight drops so one might only add 20 ppm CYA per month instead of 35.

High CYA levels do not necessarily mean algae will grow. Algae needs nutrients to grow so if the phosphate or nitrate levels are low then the algae won't grow (or won't grow as quickly -- note that phosphate removers only remove inorganic orthophosphate and do not remove organic phospahtes that algae can still use, albeit slowly, to grow). If there are algeacides being used (Polyquat, linear quats, copper ions, borates) then algae growth can be prevented in spite of high CYA levels.

Obviously, his phopshate remover either didn't remove enough phosphate or more got added to the pool.

As for CYA jumping, unless it was test error (and test strips are HORRIBLE for CYA testing), remember that for every 10 ppm FC added by Trichlor it also increases CYA by 6 ppm. So even at 2 ppm FC per day chlorine usage, that's over 35 ppm CYA PER MONTH increase.

The problems with Trichlor and increasing CYA are the number one reason there are tens of thousands of pool owners on multiple pool forums desperate to get out of the loop of having to buy more and more algaecides, phosphate removers, copper ion products, etc. from pool stores in the endless and expensive game of preventing algae. When these people then find out how quickly Trichlor (and Dichlor) increase CYA and how much that reduces chlorine's effectiveness (unless the FC level is proportionately raised), then these people are really ticked off that the pool stores didn't tell them the truth, the whole truth, and nothing but the truth! Trichlor is very convenient, but that convenience comes at a cost. It's fine to use if one understands the trade-offs and how to mitigate the issues, but for many homeowners adding chlorinating liquid or bleach every day or two is OK while for others they get The Liquidator or peristaltic pumps or a saltwater chlorine generator (SWCG).

Note that The Liquidator does NOT require any power. It uses the suction from the pump for its water flow.

[Henry_R]

Is it normal to have to routinely drain the pool due to high CYA? Do people normally have to do this when they use tablets?
:
All of the incidents included the tablet feeder going empty and the pool man not getting ahead of it before it got out of hand. And in both cases when the pool man tested the water we had large excesses of phosphates >1000ppm. He used phosphate reducer, chlorine etc and it took days to bring it under control. He was fired during the last incident three weeks ago when he failed to return repeated urgent phone calls about the pool being green which began our servicing the pool ourselves. First thing we did was test the water. TC was near zero, CYA was >100 and phosphates were >1000ppm as I said at the beginning of this thread.

So why did the CYA jump up all of a sudden? If the tablet feeder is set too high for days would that perciptate high CYA? I know the man had the feeder set to a lower setting and had to turn it up some to keep chlorine levels normal. The notes the pool man was leaving indicated normal stabilizer in the 60-70ppm range so I'm trying to figure out what went wrong. Where did it get out of control that required draining to get it down?

As for the CYA level in pools, the answer depends on the specific environment for the pool. Water dilution can occur from summer or winter rains where the water overflows and gets auto-filled, for example. There is a slow breakdown of CYA by chlorine, though that's usually only a few ppm per month. If a pool is let go over the winter with the chlorine getting to zero, then bacteria can convert CYA into ammonia creating a huge chlorine demand upon opening though sometimes other bacteria convert the ammonia to nitrogen gas while algae use it for growth. So some people find that most or all of the CYA is gone when they open the pool in the spring. However, this is not a consistent effect. Also, some parts of the country have short swim seasons so there is less CYA buildup. Also, as the CYA level rises, the amount of chlorine loss from sunlight drops so one might only add 20 ppm CYA per month instead of 35.

High CYA levels do not necessarily mean algae will grow. Algae needs nutrients to grow so if the phosphate or nitrate levels are low then the algae won't grow (or won't grow as quickly -- note that phosphate removers only remove inorganic orthophosphate and do not remove organic phospahtes that algae can still use, albeit slowly, to grow). If there are algeacides being used (Polyquat, linear quats, copper ions, borates) then algae growth can be prevented in spite of high CYA levels.

Obviously, his phopshate remover either didn't remove enough phosphate or more got added to the pool.

As for CYA jumping, unless it was test error (and test strips are HORRIBLE for CYA testing), remember that for every 10 ppm FC added by Trichlor it also increases CYA by 6 ppm. So even at 2 ppm FC per day chlorine usage, that's over 35 ppm CYA PER MONTH increase.

The problems with Trichlor and increasing CYA are the number one reason there are tens of thousands of pool owners on multiple pool forums desperate to get out of the loop of having to buy more and more algaecides, phosphate removers, copper ion products, etc. from pool stores in the endless and expensive game of preventing algae. When these people then find out how quickly Trichlor (and Dichlor) increase CYA and how much that reduces chlorine's effectiveness (unless the FC level is proportionately raised), then these people are really ticked off that the pool stores didn't tell them the truth, the whole truth, and nothing but the truth! Trichlor is very convenient, but that convenience comes at a cost. It's fine to use if one understands the trade-offs and how to mitigate the issues, but for many homeowners adding chlorinating liquid or bleach every day or two is OK while for others they get The Liquidator or peristaltic pumps or a saltwater chlorine generator (SWCG).

Note that The Liquidator does NOT require any power. It uses the suction from the pump for its water flow.

I don't think the last poolman was using strips. I remember him using a computerized device actually.
And what looked to be a DPD test kit. We are in the worst drought in years and pollen was very high in the spring. At the time the pool man accounted these two things as reason for high phosphates and algae blooms.
I don't know what he used for phosphate removal, but he was surprised that it was so high and did it three times.

I just wonder how the pool was maintained all those years before 2008 without having issues.

The managment are still refusing the do more than use Leslie's Pool store personnel advice.

I'm being blamed for doing nothing more than keeping the pool healthy to swim in AND using the chlorine feeder which I was given tablets for and told to use after we drained the pool partially. I'll take that blame however if it means nobody got sick whilst I was doing the work. There is a large misconception about whether the pool will pop out of the ground if we drain/refill again which is part of the issue over and above the water bill. We are in a persistant drought in east Tx and in particular Houston. We are 30+ inches BELOW normal in rainfall. Is there much likelyhood of the pool popping from partial draining?

Interesting abuot the liquidator. Does it require space? There is limited room for any equipment. There was a pool building with the pump, filter, etc year ago. It was torn down in 1999 and what they did was build a steel cage around the equipment barely larger than that needed for the motor, pump and filter. We had to have it cut to even remove the old filter so it could be replaced. It doesn't matter. If they won't even buy a test kit they're not going to spring for this either. Thank you for all your help and advice.

[chem geek]

I don't think the last poolman was using strips. I remember him using a computerized device actually.
And what looked to be a DPD test kit.
:
I just wonder how the pool was maintained all those years before 2008 without having issues.

A computerized device doesn't mean it is accurate. We've seen all kinds of wacko numbers from pool stores. The device could still be reading test strips or if it's reading turbidity, it would still need to be calibrated.

As for prior years, they could have been lucky or drained more water or used algaecides.

There is a large misconception about whether the pool will pop out of the ground if we drain/refill again which is part of the issue over and above the water bill. We are in a persistant drought in east Tx and in particular Houston. We are 30+ inches BELOW normal in rainfall. Is there much likelyhood of the pool popping from partial draining?

You can usually safely drain to within a foot of water in the shallow end, but there is always the sheet method where you take a large plastic sheet and drain from underneath while filling above the sheet and there's also continuous drain/refill where you drain from the bottom of the deep end while filling at the top of the shallow end with the pump off.

Interesting abuot the liquidator. Does it require space?

It doesn't require very much space as it's 14"x14" square and 29" high for the 8-gallon model. However, as you point out, it's a moot point since the HOA will never go for it.

[Henry_R]

I don't think the last poolman was using strips. I remember him using a computerized device actually.
And what looked to be a DPD test kit.
:
I just wonder how the pool was maintained all those years before 2008 without having issues.

A computerized device doesn't mean it is accurate. We've seen all kinds of wacko numbers from pool stores. The device could still be reading test strips or if it's reading turbidity, it would still need to be calibrated.

As for prior years, they could have been lucky or drained more water or used algaecides.

There is a large misconception about whether the pool will pop out of the ground if we drain/refill again which is part of the issue over and above the water bill. We are in a persistant drought in east Tx and in particular Houston. We are 30+ inches BELOW normal in rainfall. Is there much likelyhood of the pool popping from partial draining?

You can usually safely drain to within a foot of water in the shallow end, but there is always the sheet method where you take a large plastic sheet and drain from underneath while filling above the sheet and there's also continuous drain/refill where you drain from the bottom of the deep end while filling at the top of the shallow end with the pump off.

Interesting abuot the liquidator. Does it require space?

It doesn't require very much space as it's 14"x14" square and 29" high for the 8-gallon model. However, as you point out, it's a moot point since the HOA will never go for it.

I do know he was using what looked to be a normal DPD test. I think he used the electronic gizmo when he was checking the phosphates maybe.
I don't remember seeing him use any strips ever. I'm not sure though and I never will be.

I am sure the pool has not ever been drained in the last 10 years or at least not enough to be noticed. However, the man was actually fired for sticking the hose in the pool each week and just leaving it to overflow. Perhaps that was sufficient dilution to keep the CYA in check? At the time several of us complained about this thinking it a waste of water. Not long after this the man was fired.
Would hyperchlorinating weekly consitute "strong chemical in use"? The man had a wooden sign he put on the pool fence on Mondays when he cleaned the pool. Perhaps he just shocked the snot out of it and didn't use the feeder. How far back did the start making Rainbow Lifeguard feeders? It looks like this feeder is quite old really. Maybe it was installed but not used. I'm beginning to think not and wishing we'd never used the tablets either. They worked fine when no one was swimming, but seem to be an eternal thorn in my a$$ now.

I figured as much about the shell not popping out. Especially with our water table nearly zero.
That's an interesting method with the sheet.

The photo attached shows the area around the pump and filter. This is however an old picture from 2009. Way before we had a new filter and valve installed this past May. But it illustrates the space we have around the pump and filter. If I could convince the powers-that-be to install a Liquidator, do you think it would even fit? The opening is roughly and barely 24" wide. Or would we have to have some repiping to accomodate it?
We have a new filter unit and multiport valve, but otherwise the pump and motor are still positioned as shown.

[chem geek]

Perhaps that was sufficient dilution to keep the CYA in check?
:
Would hyperchlorinating weekly consitute "strong chemical in use"?
:
How far back did the start making Rainbow Lifeguard feeders?
:
If I could convince the powers-that-be to install a Liquidator, do you think it would even fit? The opening is roughly and barely 24" wide. Or would we have to have some repiping to accomodate it?

His water overflow dilution would have helped, but if he shocked the heck out of the pool every week then that would have killed off any algae that would have otherwise started to grow. In fact, many people who use Trichlor shock their pools weekly and is one of the reasons they get away with no having algae grow in spite of higher CYA levels. However, at some point, even that may not help depending on water dilution and algae nutrient levels. I don't know how old the feeders are, but having inline chlorinators for Trichlor is not new.

I think The Liquidator would fit based on its base dimensions and what you wrote as the space available -- somewhat tight, but would fit nevertheless. The Liquidator works by taking flow from the output side of the pump so a small hole is drilled into that existing pipe, and then the output of The Liquidator goes into the suction side of the pump usually via the inlet screw at the bottom of the pump basket, though drilling another hole into the suction piping is another option. If they agree to this, be sure to get the upgrades via the link I gave to you. Note that you would still need to go out and buy chlorinating liquid to refill the unit, but probably would not need to fill it more than once a month, depending on your chlorine demand -- worst case, every 2 weeks though could easily just be checked once a week. You pretty much had to do that anyway with the Trichlor tabs for the inline chlorinator.

Note that the main issue with The Liquidator is the accumulation of "white stuff" which is calcium carbonate at the output valve. The upgraded hardware helps with that and with sustaining sufficient flow, but the use of 50 ppm Borates for the pool (see So you want to add borates to your pool--Why and How) will help and will also help stabilize pH in the pool and is also a mild algaecide. Making sure the saturation index doesn't get much above 0 also helps (The Pool Calculator can calculate the saturation index for you).

[Henry_R]

Perhaps that was sufficient dilution to keep the CYA in check?
:
Would hyperchlorinating weekly consitute "strong chemical in use"?
:
How far back did the start making Rainbow Lifeguard feeders?
:
If I could convince the powers-that-be to install a Liquidator, do you think it would even fit? The opening is roughly and barely 24" wide. Or would we have to have some repiping to accomodate it?

His water overflow dilution would have helped, but if he shocked the heck out of the pool every week then that would have killed off any algae that would have otherwise started to grow. In fact, many people who use Trichlor shock their pools weekly and is one of the reasons they get away with no having algae grow in spite of higher CYA levels. However, at some point, even that may not help depending on water dilution and algae nutrient levels. I don't know how old the feeders are, but having inline chlorinators for Trichlor is not new.

I think The Liquidator would fit based on its base dimensions and what you wrote as the space available -- somewhat tight, but would fit nevertheless. The Liquidator works by taking flow from the output side of the pump so a small hole is drilled into that existing pipe, and then the output of The Liquidator goes into the suction side of the pump usually via the inlet screw at the bottom of the pump basket, though drilling another hole into the suction piping is another option. If they agree to this, be sure to get the upgrades via the link I gave to you. Note that you would still need to go out and buy chlorinating liquid to refill the unit, but probably would not need to fill it more than once a month, depending on your chlorine demand -- worst case, every 2 weeks though could easily just be checked once a week. You pretty much had to do that anyway with the Trichlor tabs for the inline chlorinator.

Note that the main issue with The Liquidator is the accumulation of "white stuff" which is calcium carbonate at the output valve. The upgraded hardware helps with that and with sustaining sufficient flow, but the use of 50 ppm Borates for the pool (see So you want to add borates to your pool--Why and How) will help and will also help stabilize pH in the pool and is also a mild algaecide. Making sure the saturation index doesn't get much above 0 also helps (The Pool Calculator can calculate the saturation index for you).

If I were doing this for a private pool of my own I'd install the Liquidator and be done with it. But my HOA Board is dysfunctional and still not listening to me at all. At some point the Board members might be different perhaps down the road. For now, they're still insisting on using Leslie's pools for advice/water testing and so far the pool is remaining clear. We need to vacuum a bit, but it's not a serious need. I've read through those articles on using Borates. There's no way I'm going to convince them to do that. I wish. The pool calculator has got me through when I was maintaining this pool in 2009. It's a valuable resource. It actually indicates the saturation index is such that scaling might occur given the reading of CH=500 and the rest I plugged into it on Saturday. I've also relayed this information and have been ignored. I just hope they're not taking the pool store advice that chlorine >5ppm is "high" and letting it decay too much. Thanks again for you help and advice.

[bluewaterpoolguy]

Sounds like to me id just try a flocculant. if it started green and you shocked and killed all that algae, its bleached out and still in the pool as a sand filter cant filter that fine of a particle. so a flocculant will help weigh those particles down and stick together for an easy vacuum.