Question: auto fill connected to water softener sys (Potassium)

Dirk

Gold Supporter
TFP Guide
Nov 12, 2017
7,208
Central California
Just so it's said: you don't add salt for at least a month. I filled my pool about this time of year, and didn't add salt until Spring. My SWG wouldn't have worked in the winter anyway, so I figured if waiting to put in salt for a month is good, waiting until spring would be even better. I ran my pool as a non-swg pool during that first winter, using liquid chlorine. Then fired up the SWG when temps warmed up.
 
  • Like
Reactions: JC707

JC707

Well-known member
Sep 5, 2020
127
Bay Area, CA
Thanks Dirk...luckily I have until spring 2021 to get everything noted and learned here. I was reading some builders don't install the SWCG until after 30 days and you just use liquid chlorine until then?
 

JoyfulNoise

TFP Expert
Platinum Supporter
May 23, 2015
17,378
Tucson, AZ
Joy,
Are you sure your regen takes that long. I have an aquapure softener installed approx 7 years back and the regen is 1:05 (65 min)
My water softener is made by WaterTec which a local Tucson business. They manufacture their own resin tanks and systems but use Clack valves. My unit has a separate 160lbs brine tank (ie, it holds 4 x 40lbs bags of salt). The unit is a 52k grain softener with a GAC filter to remove chlorine/chloramine/VOCs/etc. The regen cycle uses several backwash and rinse steps (to mix up and churn the resin so it doesn’t settle and compact). The brine creation step add about 8 gallons of water to the brine tank and then it sits in there for about 2 hours before drawing the brine solution back into the softener tank to exchange ions. The “brine creation” step is the longest in the process but it’s length ensures that the brine water is completely saturated with salt before it is used to treat the resin. Exchange resins work only when the concentration of the soft ion (Na+) is much, much greater than the mineral ion (Ca++) because the softener resin will have slightly greater affinity for calcium. If your brine solution is not fully saturated, there can be incomplete exchange. There’s a whole spectrum of variables when it comes to ion exchange (media chemistry, brine saturation, temperature, contact volume, pH, etc, etc, etc). All these parameters have to be optimized to get efficient exchange in a reasonable time. As such, different manufacturers will have different process times. Mine is a little over 2 hours.
 

wireform

Silver Supporter
In The Industry
Aug 15, 2017
1,582
Spring Valley, NY
My water softener is made by WaterTec which a local Tucson business. They manufacture their own resin tanks and systems but use Clack valves. My unit has a separate 160lbs brine tank (ie, it holds 4 x 40lbs bags of salt). The unit is a 52k grain softener with a GAC filter to remove chlorine/chloramine/VOCs/etc. The regen cycle uses several backwash and rinse steps (to mix up and churn the resin so it doesn’t settle and compact). The brine creation step add about 8 gallons of water to the brine tank and then it sits in there for about 2 hours before drawing the brine solution back into the softener tank to exchange ions. The “brine creation” step is the longest in the process but it’s length ensures that the brine water is completely saturated with salt before it is used to treat the resin. Exchange resins work only when the concentration of the soft ion (Na+) is much, much greater than the mineral ion (Ca++) because the softener resin will have slightly greater affinity for calcium. If your brine solution is not fully saturated, there can be incomplete exchange. There’s a whole spectrum of variables when it comes to ion exchange (media chemistry, brine saturation, temperature, contact volume, pH, etc, etc, etc). All these parameters have to be optimized to get efficient exchange in a reasonable time. As such, different manufacturers will have different process times. Mine is a little over 2 hours.
My softener starts the brine right after the regen completes and just sits there to the next regen. Maybe that's where the time is less.
 
Last edited:
  • Like
Reactions: JoyfulNoise

HermanTX

Gold Supporter
May 20, 2020
782
Katy TX
I looked at water softener and it takes overall 90 mins to re-gen with rinses, etc. It starts at 2am. I can bypass the whole unit and I can cut off water to the whole house with it but it will also cut off my fill line. I cannot selectively bypass the house and keep the fill line open. Maybe something I need to look into.
 

JC707

Well-known member
Sep 5, 2020
127
Bay Area, CA
Update - I have the water softener guys over performing my yearly maintenance and asked if my system was large enough to handle an auto fill feature for our new pool.

He said we have the lower rated system, won't be large enough to handle auto filling feature of pool. He said I would blow thru the resin and potassium like crazy and need a larger system they have.

I asked him if they could give me credit for the system we have now since we installed only 2 years ago and install the larger system, he is going to get back to me. Fingers crossed 🤞
 

JC707

Well-known member
Sep 5, 2020
127
Bay Area, CA
This larger system is $7,000...even if they can give us some credit for our current system (paid $5,000), will be a hard sell for my wife.

What are other options to do auto fill? We have that 1 hose bib out back that is connected to water softener and then sprinkler drip lines that run out back which we may be getting rid of due to pool install.

Can we do an autofill from a sprinkler valve?
 

scottts

Gold Supporter
Nov 13, 2019
161
Gilbert, AZ
How much autofill water is needed per month in the Bay Area? What's the grain rating of your softener? What's the hardness of your supply water? If you're just using the softener for autofill make up water and not an initial pool filling, I don't think the average evap is going to "blow through" any reasonable sized softener.
 
  • Like
Reactions: TampaKathy

JC707

Well-known member
Sep 5, 2020
127
Bay Area, CA
How much autofill water is needed per month in the Bay Area? What's the grain rating of your softener? What's the hardness of your supply water? If you're just using the softener for autofill make up water and not an initial pool filling, I don't think the average evap is going to "blow through" any reasonable sized softener.
Thanks for the reply. I am going to research those questions and get right back to you. I do know we have a decently sized system right now....maybe he is just trying to upsale me. He did say he has a pool at his place and uses this same system he is recommending to me.
 

mknauss

Mod Squad
TFP Expert
Bronze Supporter
May 3, 2014
33,371
Laughlin, NV
Bay Area is pretty general. If in Pacifica, you will not get much evaporation if the pool is covered (cold air, warm water). If in Tracy, you will get more evaporation due to low humidity and wind.
 

scottts

Gold Supporter
Nov 13, 2019
161
Gilbert, AZ
The second row, Hardness Capacity, is the important number. Each regen of your softener has a capacity to exchange 30,200 grains of harness. If you can find out how many grains per gallon your feed water is then you can figure out how many gallons each regen can soften. Then you can estimate your pools makeup water needs, add in your household use, and figure out how often the softener would need to regen.

For example, if your water is 10gr/gal then each regen can soften about 3000 gallons. So your system would regen every time your house + pool used 3000 gallons of water.

Oops, the specs changed as I was responding. Same concept, though.
 

JC707

Well-known member
Sep 5, 2020
127
Bay Area, CA
Ahhh makes sense! I will find out how hard the city water is shortly. I believe he tested it when he was out here...if not I will test it myself.
 

scottts

Gold Supporter
Nov 13, 2019
161
Gilbert, AZ
Those numbers are telling you how many grains of harness can be exchanged if you regen with various amounts of salt. Some systems have multiple operating modes and softening is more salt efficient if smaller regens are done. But then the system regens more frequently. Its a trade off. You can regen less but use more salt, or regen more often and use less salt. These could be ratings for your tank and resin. It doesn't necessarily mean you can chose to operate in any or all of these modes..
 

JC707

Well-known member
Sep 5, 2020
127
Bay Area, CA
Really appreciate the help scott. I was playing with the settings and came across this number. Shows 397 gallons remaining (61%) until next regen I am assuming. Need to find the manual they gave me its buried somewhere lol.

If I compute this out... it would be approx 650 gallons per regen? Seems low 🤔
 

Attachments

scottts

Gold Supporter
Nov 13, 2019
161
Gilbert, AZ
My guess is that's what its saying. Somewhere in your system's menus you should be able to see what the hardness setting is, what salt type your using (potassium) and what efficiency mode you are set for. You may be set for high efficiency operation and a high hardness level. Also, if you water has iron in it that can cause you to have to regen more often. A ppm of iron is usually considered equivalent to 3 grains hardness.
 

JoyfulNoise

TFP Expert
Platinum Supporter
May 23, 2015
17,378
Tucson, AZ
You will not "blow through your resin..." or whatever he said, he's trying to up-sell you. Adding a pool autofill line is the approximate equivalent of adding another human being to your household water use. So you will need to regenerate more often.....

.... however, there is a BIG caveat ....

Most residential water softeners measure flow to trigger regeneration but they do so at household pressures and flow rates. Most faucets and toilet tanks fill at a rate of about 1 GPM or higher. So the flow meter inside the softener that counts volume used is designed around that residential flow rate. Most pool autofills dribble water into a nearly full pool at an MUCH MUCH LOWER flow rate than an open spigot or water faucet. Therefore, even though water will trickle through your softener and get the hardness removed, I doubt your unit will detect it or count it.

This is important because it means you have to consider a higher value for the "reserve volume" setting on your softener. Reserve volume is basically the difference between the absolute amount of water a softener can process (total grains removed divided by the input water grains/gallon) and the volume set point you use to touch off regeneration. For example, if your softener can process 1000 gallons of water in total before needing regeneration, you would likely set your system to regenerate at 800 gallons of use and leave 200 gallons in reserve. If a slow trickling autofill is involved, you might want to have a higher reserve of say 250 gallons or 300 gallons so that you don't exhaust your softener before it regenerates.
 

JC707

Well-known member
Sep 5, 2020
127
Bay Area, CA
Thanks Joyful!! This is actually great news as we could not drop $4000+ for a larger system.

I have a regen coming up tomorrow at 2am and will check what the system shows for remaining gallons afterwards. I will also find the owners manual around my house somewhere and see what settings I can change. I am hoping I can play around with the regen settings so I can change it to regen at a lower number to leave a larger reserve. Lastly I will find out my fill water hardness level.

Dumb question but as it stands now....when they installed unit, there is no reserve used is that correct? Or is there always a reserve left in even if they know the home owner has no pool?
 

BowserB

Silver Supporter
Jul 29, 2018
363
Katy, Texas
I had a potassium based softener for a year before our pool was finished. Now I've had the pool for two years and a month. For the initial fill, I put the softener on bypass. Only our sprinkler system is upstream of the softener, so the hose bibs are soft water--another reason we chose potassium over sodium chloride. The autofill is connected to one of the hose bibs, and it has been our only water addition except for rain. I do on occasion have to add calcium to the pool to get the CH at least up to minimum. I'm an accountant by education, and anything I could do to avoid adding soft water to the pool will cost many times what I spend on calcium.

And once again, I hear prices for stuff I buy that are better elsewhere than in Houston. Houston Lowes is $32 for a 40 lb bag of potassium salt. However, a Texas grocery chain, HEB, sells Morton potassium salt for $24. They don't always have it in my store, so when they do, I stock up. Still it boggles the mind that the Bay Area of California Lowes would have potassium cheaper than Houston Lowes. Houston is also apparently a hot spot of liquid chlorine, as it seems to be cheaper everywhere than it is in Houston. One Leslies sells 4 gallons of 12.5% for $17, but others sell it for $20. I see east coast and California prices all lower. Gasoline is a bit cheaper here, but we hardly use any lately. :)