$17.98 for 2 pack of HDX chlorine from home depot.

Newdude said:

Guesstimates make things screwy.

$3.77 (steal of a deal price) per gallon of 12% equals $0.78 per FC for your 25k gallons.

That is both stronger and cheaper than most will find, and it's still 50% more than an IC40 over its lifespan.

I went IC40 for you with a short and easy UV season up north. $1500 for the complete system will get 2791 FCs lifetime in 25k gallons. $0.53 each.

If you pay someone $500 to install it, it's $0.71 per FC for the first unit, which is still cheaper than your steal of a deal liquid shock. Future cells would be minus the install fee, and controller fee, and very much in your favor.

Put another way, each gallon of 12% gets you 4.8 ppms. And IC40 is equivalent to 581 gallons, which would cost you $2192 at the steal price.

*not lugging 581 jugs...... PRICELESS

Click to expand...

Yeah, rereading my post, I kinda gave the wrong impression - trying to do two things at once

What I meant to say was even at such a low price for Liquid Chlorine (under $4/gal for 12%), a SWCG would still end up being cheaper than I'm currently paying, even allowing for a new pump and replacement cells (which are barely more than I pay for one season's worth of LC).

If I was paying twice as much for my Chlorine, the math only favors the SWCG more and more.

However, hard to throw $3k at the pool this spring when I just threw $15k at the roof...and carrying those jugs is about all the excercise I get !!

Dang. Price at my local home depot here in DFW lists the 4-gal box of Pool Essentials 10% at $29.98. Last time I stocked up, it was $17.98. The palette still had a shipping label on it last time, and indicated it had shipped from Florida. I wonder if Hurricane Ian had something to do with this rapid price increase.

Newdude said:

Ahhhh..... yes....... the drought....... *pays double for spaghetti sauce*

Click to expand...

Well, I have heard rumors that the spaghetti harvest wasn't great this year...

Yeah it is getting ridiculous, time for a new source/ SWCG

jake556 said:

<snip>
Yeah it is getting ridiculous, time for a new source/ SWCG

Click to expand...

I mean, it's not even 12%...and I was paying less than that for FOUR gallons
That's not a supply chain issue, or consequence of inflation, it's just greed, plain and simple.

Probably explains why the stack at Menards turned over so quickly tho - glad I still have 5-6 gallons in the 60F well room!

JeanZ1 said:

TDS range for SWG pools is higher because salt is a dissolved solid, you add salt and TDS increases so the range has to reflect that.

Click to expand...

My point of view is... if the cited suggested ranges on TDS are intended to be important enough to matter, then they should matter the same whether or not the pool is a SWCG or not.

Given that logical argument, I then agree with the post that said the cited TDS ranges don't matter - which means those cited suggested TDS ranges are likely nearly meaningless in terms of how to treat a pool (other than they play an equally minor role in the saturation calculations, SWCG or not).

Newdude said:

I went IC40 for you with a short and easy UV season up north. $1500 for the complete system will get 2791 FCs lifetime in 25k gallons. $0.53 each.
Future cells would be minus the install fee, and controller fee, and very much in your favor.
Put another way, each gallon of 12% gets you 4.8 ppms. And IC40 is equivalent to 581 gallons, which would cost you $2192 at the steal price.

Click to expand...

You make a compelling logical objective argument that the price per effective chlorine via SWCG could be less than that of trading HASA cases by the trunkful.
Even with the 5 to 7 year replacement and 20 to 25 year replacements scheduled.

I would do all the SWCG installation myself as would I be doing all the maintenance, repair, and replacement, so the prices that matter are that of the equipment.

There are ancillary operating costs of course, such as additional salt & electricity for SWCG versus additional gasoline & storage costs for HASA trades, which, I hope we can presume is a wash?

RickRude said:

Dang. Price at my local home depot here in DFW lists the 4-gal box of Pool Essentials 10% at $29.98. Last time I stocked up, it was $17.98. The palette still had a shipping label on it last time, and indicated it had shipped from Flor

Click to expand...

I happened to be in Home Depot this afternoon and snapped a photo of the current prices for the 10% HDX chlorine ($9/gallon) & 14.5% HDX HCL ($8.50/gallon).
At $17.98 for two gallons, the calculation turns out to be $0.11/pound of available chlorine (not even counting about 10% sales tax of about $1.50).

• 10% Trade% liquid chlorine: $cost/gallon x 1gallon/9.4pounds x 1/8.77% available chlorine (by weight) = price per pound of available chlorine
• $18/2 gallons x 1 gallon/9.4 pounds x 1/8.77% available chlorine by weight = $0.11 per pound of available chlorine (if I did the Richard Falk math correctly)

TDS can be somewhat valuable in identifying dissolved solids that are not salt and that are unknown as to exactly what they are.

For example, if you get a TDS reading (Meter set to Salinity only) and then you subtract all known components like salt, calcium, cyanuric acid etc. and there is still a large amount of unknown dissolved solids, it might indicate the need to replace the water.

The real concern is if there is a large amount of unidentified dissolved solids and you can’t identify the solids, they might be something that affects the water quality.

Some dissolved solids that are not usually measured are magnesium, potassium, sodium, sulfates, lithium, aluminum, iron, phosphate, copper, nitrate, zinc etc.

Assuming that people are filling their pools from a quality source, they would almost always find that the TDS (Meter set to Salinity only) can be almost 100% accounted for by measurable components.

Note that when using a meter set to TDS, the assumption is that the water is adequately represented as “Natural Water Standard Solution. 40% sodium sulfate/40% sodium bicarbonate/20% sodium chloride”.

When testing pool water, the TDS setting on a meter is not appropriate.

Only the Salinity setting is appropriate.

If you get a reading on a Salinity meter and the number is way higher than the sum of all measurable components, that would indicate that there are unknown contaminants in the water.

For a residential pool with good water quality, measuring TDS is rarely necessary.

If you use a salinity meter as a standalone meter or from a reading from a SWG like the Intellichlor or the Aquapure, you can compare the salinity measurement to a measurement of salt from a chloride specific test such as a K-1766.

These readings should match to a good degree when accounting for other components such as calcium and CYA.

If these reading were significantly off or if the water had issues that were not responding to normal remediation procedures a TDS test could help diagnose what the problems were.

I only remember one case on this board where the TDS reading indicated an issue.

The pool had flooded with dirty water and the pool was having issues that were not responding to normal protocols.

The TDS was way higher than the sum of all measured components, which indicated a contamination of some sort of unknown dissolved solid.

Significant dilution was recommended.

Instead of a TDS limit, the limit should be for “Unidentified TDS” components.

For a high use commercial pool, a regular TDS measurement would be worthwhile and will sometimes be required by the health department.

High bather loads introduce a lot of contaminants because people are covered in a variety of compounds like suntan lotion, hair products, makeup, dirt, deodorant, antiperspirant etc. as well as excreting various compounds like sweat, urine, skin cells, saliva etc.

Urine and sweat can also contain various compounds like drugs (legal or illegal) that pass through in the urine or sweat.

High use commercial pools, especially indoor pools will begin to develop disinfection by-products, which are formed when disinfectants like chlorine interact with natural organic materials in water.

Disinfection by-products include products like trihalomethane, haloacetic acid, bromate etc.

Tracking "Unidentified TDS" can help a commercial pool operator know if the water quality is being affected by unknown contaminants.

High use commercial pools should use dilution to help manage water quality.

Tracking unidentified TDS can help a commercial pool operator know if the water is being adequately diluted.

JamesW said:

The real concern is if there is a large amount of unidentified dissolved solids and you can’t identify the solids, they might be something that affects the water quality.

Click to expand...

This is the first explanation that begins to make logical sense of why the TDS limits on multiple sites are DIFFERENT for normal pools versus for SWCG pools.

What confused me is that multiple sites have DIFFERENT ranges but none of them EXPLAIN why the ranges would be different.
Your explanation makes sense.

For example, let's say we have to identical pools other than one is SWCG and the other is normal.

• Then assume we throw into both pools the same large amount of an "unidentified dissolved solid"
• That addition of "unidentified dissolved solid" would raise the TDS ppm the same in each pool

However, if the "ideal" TDS ranges are the same for both pools, then the same amount of added unidentified dissolved solids could easily knock the SWCG pool out of range simply because that pool is already higher within the ideal range due to its inherent salt content.

On the other hand, given the TDS "ideal" range is (often cited to be) higher (& perhaps even wider) for SWGC pools, the same amount of unidentified dissolved solid could easily put either the normal pool out of the recommended TDS range or it could put the SWGC pool out of the recommended TDS range, depending on the PERCENTAGE of the range of unidentified dissolved solid that was added.

Even worse, the fill water TDS value can be completely different for any given pool, mostly dependent on location.

It's all so confusing (to me) but I guess that's why some of the better charts give a TDS PPM limit of something like "1,500 PPM above startup levels", which requires each pool owner to maintain a log of the startup levels for any given five to seven year pool water fill but which allows each owner to have a DIFFERENT normal starting condition (which takes into account the fill water source and the type of chlorination).

Other than LC raising the TDS slightly (the pH not being a real factor overall), the disadvantage of LC (as everyone with a SWCG pool will mention), is that it's a PITA to lug to and fro. To that end, I opened a new thread today asking if it's possible to ameliorate that one issue with SHIPPING of liquid chlorine, to your home, in residential quantities.

• Shipping of Liquid Chlorine to your Home

When I installed a SWG at the beginning of the summer, I created a detailed spreadsheet to compare LC costs to my Hayward SWG.

The SWG cost was based on buying a new, complete SWG system, and installing myself. I included electricity costs for the SWG.
Came out to $3.76 per gal of LC. At the time LC was $5 per gal at HD, so I was ahead back then, way ahead now at $9/gal.

SWG costs included just under $2000 for the Hayward, $80 salt, $150 pipe and stuff and $400 in electricity. Looking at Leslies, W3AQR15 is same price as when I bought it after you add in CA sales tax.
I used the rated life of 580 pounds of chlorine from my swg cell for my calculations.

When I have to replace the cell, if it costs $1000 to replace it, costs go down to about $2/gal.

I think Hayward is on the pricier side for SWG's too, but I wanted a Hayward SWG so I could integrate into my pool automation system.

And it was so much easier to take care of the pool this summer with SWG. Only sorry I didn't do it sooner.

Randy

randytsuch said:

When I installed a SWG at the beginning of the summer, I created a detailed spreadsheet to compare LC costs to my Hayward SWG.

Click to expand...

I like that you're in California, which has an almost 10% surcharge on everything (due to sales tax), which you accounted for, which I appreciate.
And you accounted for maintenance cost, which is critically important, as the initial cost isn't even close to the total cost for SWCG pools.
Likewise, you accounted for installation cost, which, at least for me, would be nearly zero as I'd do all the work myself (unless I can't).

On the other side, there are also large costs such as transportation cost & storage degradation cost to lugging HASA cases around (not to mention potential leakage damage to vehicles).

But there's a potentially large cost to SWCG pools that I don't see well fleshed out, yet.

• Electricity

Given my pumps are decades old, they're single speed and given it's a self cleaning pool, there are two pumps (one for the self cleaning popups and the skimmers, and the other for the filtration), I barely use the pumps (the load on my pool is nearly zero so the water stays crystal clear).

Even more to the point, in the winter, I don't run the pumps at all, and the water currently is 53 degrees but it will go at least ten or fifteen degrees lower over time, so the FC level remains relatively easy to manage.

Without using the pumps (due to the high cost of electricity), I clean the pool manually with a skimmer net and a garden hose vacuum attachment.
(The bather load is nearly zero.)

But the one thing I have plenty of, is sunshine... which (as you know) drastically affects the HASA LC FC rate (even with my 30 ppm CYA).

In California, electricity rates have a rather complex set of tiers based on either usage per month or on time of day and day of week and summer/winter rates, and rates based on the heating type of the home, and rates based on adjustments due to our selection of who generates the power (aka "generation credit") and who distributes it, and people with solar panels have different rates (I don't have panels), so no two people have the same rates, but I do have my latest bill in front of me.

• My peak rate in September was $0.47427 per kWH (peak being from 5pm to 8pm weekdays)
  • My peak rate in October was $0.38466 per kWH
• My September off-peak rate was $0.33931 per kWH (offpeak being all other times, including holidays)
  • My October off-peak rate was $0.34605 per kWH

It's hard to average that out, but if we needed one number, how's somewhere between 35 and 40 cents per kilowatt-hour sound?

As noted, that's not the total charge as taxes and fees and surcharges are added, but that's the direct cost per kilowatt hour of usage for my type of plan (again, many plans exist which have completely different tiers and prices - but no tier will be anywhere near the national average - they're all going to be some of the highest prices per kilowatthour in the nation).

Using just those numbers, how much does it cost to run the electricity for a typical SWCG pool?

Gary Davis said:

I like that you're in California, which has an almost 10% surcharge on everything (due to sales tax), which you accounted for, which I appreciate.
And you accounted for maintenance cost, which is critically important, as the initial cost isn't even close to the total cost for SWCG pools.
Likewise, you accounted for installation cost, which, at least for me, would be nearly zero as I'd do all the work myself (unless I can't).

On the other side, there are also large costs such as transportation cost & storage degradation cost to lugging HASA cases around (not to mention potential leakage damage to vehicles).

But there's a potentially large cost to SWCG pools that I don't see well fleshed out, yet.

• Electricity

Given my pumps are decades old, they're single speed and given it's a self cleaning pool, there are two pumps (one for the self cleaning popups and the skimmers, and the other for the filtration), I barely use the pumps (the load on my pool is nearly zero so the water stays crystal clear).

Even more to the point, in the winter, I don't run the pumps at all, and the water currently is 53 degrees but it will go at least ten or fifteen degrees lower over time, so the FC level remains relatively easy to manage.

Without using the pumps (due to the high cost of electricity), I clean the pool manually with a skimmer net and a garden hose vacuum attachment.
(The bather load is nearly zero.)

But the one thing I have plenty of, is sunshine... which (as you know) drastically affects the HASA LC FC rate (even with my 30 ppm CYA).

In California, electricity has tiers and summer/winter rates, and rates based on the heating type of the home, and rates based on adjustments due to our selection of who generates the power (aka "generation credit") and who distributes it, and people with solar panels have different rates (I don't have panels), so no two people have the same rates, but I do have my latest bill in front of me.

• My peak rate in September was $0.47427 per kWH (peak being from 5pm to 8pm weekdays)
  • My peak rate in October was $0.38466 per kWH
• My September off-peak rate was $0.33931 per kWH (offpeak being all other times, including holidays)
  • My October off-peak rate was $0.34605 per kWH

As noted, that's not the total charge as taxes and fees and surcharges are added, but that's the direct cost per kilowatt hour of usage for my type of plan (again, many plans exist which have completely different tiers and prices).

Using just those numbers, how much does it cost to run the electricity for a typical SWCG pool?

Click to expand...

Your electricity costs would depend on your pump, and your rates which you provided.
The electricity used depends on the HP of the pumps.
The SWG itself uses $414 worth of electricity to create the 580 pounds of chlorine that my SWG cell is rated for, so basically the life of cell.
My electricity costs is 25 cents per kWH, so less than your rates. Figure you'd pay about $600 for the electricity for the SWG plus cost of running the pump.

LA DWP had a great rebate to convert to a VSP, does your electric company offer a rebate?
Do you have to run both pumps, or can you just run the circulation pump? If you just needed one to circulate water for the SWG, and you convert to VSP, might still save money.

Randy

Newdude said:

A 1x SWG needs to run 24/7 during the peak season and less before/after.
A 2X SWG needs to run 12 hours a day during the peak season and less before/after
A 3X SWG needs to run 8 hours a day during the peak season and less before/after.

Click to expand...

I know so little about SWCG pools that I don't even know what 1X, 2X, 3X mean, but I can still glean from your helpful reply that my pump usage would jump from almost zero per month (zero for the entire winter) to something much higher - which wouldn't be as big a jump for most people who use their pumps (or who have more modern setups - which I admit - mine is the old style single-speed electricity gulpers - which is why I don't use them unless I must).

Newdude said:

My pump is on 24/7 because we like the look of the moving water. I'm also too lazy/forgetful to worry about a schedule. So my pool would be running either way for about $20 a month and the SWG doesn't add any runtime.

Click to expand...

I'm guessing my pumps each run at somewhere around 3 to 6 amps at 220VAC but I could check if that amperage seems off to others.

Assuming those numbers, that's 6 to 12 amps x 24 hours per day, times 30 days per month is about 4,320 to 8,640 watts which, even if all of it was at the lowest rates in my bills (34 cents per kilowatt-hour), comes to thousands of dollars per month for the SWCG electricity alone.

My rough calculation must be off because that seems prohibitively high just for the added electricity alone.

Of course, nobody would run my inefficient pumps at California electricity rates, where most people would replace the pumps with more efficient pumps (instead of not running them, which is what I do).

We'd want the SWCG electrical cost calculations to be realistic for most people in California - not just me.

So what I'd need to come up with is a realistic amount of electricity a SWCG pool would cost me over and above the almost zero that I'm using now because I self maintain the pool by manual skimming, brushing to the deep end, and then vacuuming the deep end with a garden hose attachment.

Almost certainly, whatever pump runs the water through the SWCG would need to be upgraded to a variable flow pump, is that right?

Newdude said:

With a single speed pump and a smaller SWG, increasing pump runtime from 4-ish hours a day to 24/7 could easily be $100+ a month in electric for most of the country.

Click to expand...

Based only on my calculations above, just adding only a SWCG would add thousands of dollars per month to just the cost of added electricity required; but maybe my calculations are off?

I admit I'm not typical in that I don't use my pumps at all most of the time - expressly BECAUSE of the high cost of electricity in California.

Two critically important questions for SWCG pools need to be fleshed out to determine if they're worth it:

• What's the average cost of electricity (by the kilowatt-hour) in any given area?
• What's the average increase of electricity (in kilowatthours) needed for SWCG pools?

If there is no increase in electrical use, then the monthly electricity cost for SWCG can be ignored.
But if there is an increase in electrical usage, then the additional cost of electricity for SWCG shouldn't be ignored in the cost calculations.

Gary Davis said:

Assuming those numbers, that's 6 to 12 amps x 24 hours per day, times 30 days per month is about 4,320 to 8,640 watts which, even if all of it was at the lowest rates in my bills (34 cents per kilowatt-hour), comes to thousands of dollars per month for the SWCG electricity alone.

Click to expand...

12 amps x 230 volts is 2,760 watts or 2.76 kilowatt-hours per hour.

That's 66.24 kilowatt-hours per day at 24 hours.

That's $22.52 per day (at $0.34 per kilowatt-hour) or $675.65 per 30 days.

Note that power is measured in watts or kilowatts and energy is measured in kilowatt-hours.

Power is the rate of energy use.

Your bill is based on the amount of energy you use.

Easy answer is add a SWCG at the same time you switch to a VSP. Single speed pumps are relics of a bygone era. For a CA-based user, the ROI in switching to a VSP would be very very short.

I run ~1400rpm's 24/7 at 196 watts (each hour) currently. Really makes managing a pool super easy - just have to remember seasonally to punch a few buttons on the SWCG to raise or lower output.

A SWG uses about 150 watts, so about 5 cents per hour (at $0.34 per kilowatt-hour), $1.22 per day or $36.72 per 30 days running continuously.