Become a TFP Supporter Pool Math Forum Rules Pool School
Page 1 of 2 12 LastLast
Results 1 to 20 of 23

Thread: Idea to reduce calcium hardness

  1. Back To Top    #1

    Join Date
    Jan 2015
    Location
    Carlsbad, CA
    Posts
    6

    Idea to reduce calcium hardness

    Hi All,

    I recently let my pool guy go and I'm in the process of balancing the water. First I found that the TA is low (40ppm) so I'm addressing that by adding baking soda. Our pool has always needed to add MA to combat high PH, and I think I just discovered why...

    Next I noticed that I had absolutely no CYA as we have a SWC and our pool guy obviously didn't think we needed it. I am addressing that by adding CYA.

    I'm now in the process of trying to figure out how to reduce my CH which is at 800.

    I know the foolproof method is to drain the pool, and refill with new H20. I tested my tap water and the CH is at 350. So my plan would be to purchase a hose filter to reduce calcium, metals, etc.

    Here's my idea - I have a spigot on my pool equipment between the pump and filter. Can I hook up a hose and run the pool water through the inline hose filter over to the pool? My thought is that it would filter out alot of the CH and any metals.

    I was thinking it may be easier than draining an refilling with new H20, but I'm not sure how the other chemicals will affect the ability of the inline hose filter (ie. Salt, Chlorine, etc)...

  2. Back To Top    #2
    Richard320's Avatar
    Join Date
    Jan 2010
    Location
    San Dimas, CA (LA County)
    Posts
    18,768

    Re: Idea to reduce calcium hardness

    I've never heard of an inline Calcium filter. Got a link?

    If you're thinking reverse osmosis, it will remove everything, including salt and CYA. Reverse osmosis is also not 100% efficient - you lose maybe 25% of the water when it flushes the concentrated brine down the drain.

    I battle high CH as well, and 800 is about the limit of easy management. Since I don't have a SWG, I use pool water on the lawn and refill with what I would have used on irrigation. In your case, that's not an option.

    You ought to crunch some numbers and see how much it will cost to refill your pool. Some water companies drop the tier pricing on the water for a pool refill every few years if you arrange it in advance.
    16K freeform gunite with spa; Pentair 4000 DE filter; Century Whisperflow 1 HP; Pentair Minimax heater.
    Troublefree does not mean Maintenancefree. It's like brushing your teeth: You can spend a couple minutes a day and pennies a week or go to the dentist once a year and spend several thousand dollars.
    A pool is like a pet - you have to feed it every day, even the days you don't want to play with it!

  3. Back To Top    #3

    TFP Guide

    chiefwej's Avatar
    Join Date
    Jun 2011
    Location
    Tucson
    Posts
    2,853

    Re: Idea to reduce calcium hardness

    You can't just filter out calcium hardness. That would require either reverse osmosis treatment or a water softener.
    chiefwej
    Tucson, AZ
    16x36 rectangular (19k) Pebble Tec play pool/spa, Pentair Intelliflo VS 011018, Super II 2hp (spa), Aqua Rite T-15 SWG, Pro Grid 60 DE, Hayward H400 & Heliocol Solar heating, A&A infloor system, fill water w/high CH and TA, 50 ppm borates,TF-100 test kit

  4. Back To Top    #4

    Join Date
    Jan 2015
    Location
    Carlsbad, CA
    Posts
    6

    Re: Idea to reduce calcium hardness

    Thanks for the info on the pricing. I was going to filter the new water out of the tap with this:
    http://www.spadepot.com/shop/PreFres...-P784C632.aspx

  5. Back To Top    #5

    In the Industry

    duraleigh's Avatar
    Join Date
    Apr 2007
    Location
    Sebring, Florida
    Posts
    30,077

    Re: Idea to reduce calcium hardness

    I was going to filter the new water out of the tap with this
    : In a nutshell, it won't work. The only way to make a SIGNIFICANT reduction in CH or Iron is to make a chemical change.......not a physical one like filtration.
    Dave S.
    42k vinyl and concrete pool, 1.5hp pump, 140gpm filter
    TFTestkits , PoolMath , Pool School

  6. Back To Top    #6

    Join Date
    Jan 2015
    Location
    Carlsbad, CA
    Posts
    6

    Re: Idea to reduce calcium hardness

    If it sounds too easy it usually is right? Looks like I'll drain, refill, rebalance...

    Thank you all for your feedback!

  7. Back To Top    #7
    gtemkin's Avatar
    Join Date
    Jun 2008
    Location
    Seattle, WA
    Posts
    738

    Re: Idea to reduce calcium hardness

    It would be nice if it could work but the link you provided doesn't say it will remove calcium at all. The closest material it says it will remove is Lime Scale, which I take to mean solid chips of Lime, which is not the same a dissolved calcium.
    21K gal 16' x 40' in-ground pool built 1959, old school with Jacuzzi bronze pump, American Products 24" Sand Filter & Americana Multiport valve, Jandy Lite2 millivolt heater, Coverstar cover, and classic Kreepy Krauly.

  8. Back To Top    #8

    Join Date
    Jul 2014
    Location
    Peoria, IL
    Posts
    389

    Idea to reduce calcium hardness

    I have the same issue with CH. And I also have SWG pool. I actually get little white flakes on the bottom of the pool that tend to accumulate in the corners. This just started to get bad last year. I have the wife vacuum to waste, I backwash and rinse often (maybe more often than necessary) and the issue has seemed to resolve itself. Mainly due to the drain and refill that happens when I need to add water. I also had an outside spigot ran that runs thru my water softener in the house. It is right by the pool for this purpose. We shall see when I reopen in the spring.

    It is still crazy to me that I can have a SWG pool with 3200 ppm of salt in it and have hard water. Isn't that what a water softener does? Add salt??

    Hopefully you either got a new pool guy or you are now your own pool guy (thanks to this wonderful forum). Having no CYA in a SWG pool and not thinking to add any is an issue you should not have with a "professional".


    30x20 vinyl IG, Hayward SD60 with Pentair Dynamo 340219 2HP pump, Compupool CPSC24 SWG, Hayward H200FDN heater. APC automatic pool cover.
    Central Illinois

  9. Back To Top    #9

    In the Industry

    Donldson's Avatar
    Join Date
    Jun 2009
    Location
    NW Ohio
    Posts
    2,637

    Re: Idea to reduce calcium hardness

    Quote Originally Posted by bdex View Post
    It is still crazy to me that I can have a SWG pool with 3200 ppm of salt in it and have hard water. Isn't that what a water softener does? Add salt??
    Yes and no. It uses a special process that replaces calcium ions with sodium ions. This is accomplished by soaking plastic beads in a salt brine to capture the sodium, and then the incoming water exchanges the calcium for the sodium through processes that are above my pay grade.

    Just adding salt to water makes it "feel" softer but does not remove anything from the water.

    Also, before it is asked, you cannot hook a residential water softener to a pool circulation system. A good thought but not feasible due to the water volume needed.

    From myHTC One via Tapatalk
    JD - 28' Round Above Ground Pool, 17,000 Gallons. Dual speed Jacuzzi pump with cartridge filter. Dual speed 1 HP pump, Hayward S210T sand filter
    Pool School - PoolMath - HIGHLY Recommended Test Kits

  10. Back To Top    #10

    Join Date
    Jan 2015
    Location
    Carlsbad, CA
    Posts
    6

    Re: Idea to reduce calcium hardness

    Well I looked into having a company come out to run my water through their reverse osmosis trailer set up --- $550 bucks! I also ran some tap water through a carbon filter that I use for the RV and it tested at 250ppm. So it looks like a complete drain and refill with carbon filter and I should be good to go. Now to figure out how to drain it... wish I would have found this site before my pool was done and just maintained it myself... At least it will good from now on.
    12K gal in ground oblong concrete pool & spa built 2012, pentair equipment, DE filter

  11. Back To Top    #11

    Join Date
    Mar 2007
    Location
    San Rafael, CA USA
    Posts
    12,082

    Re: Idea to reduce calcium hardness

    Quote Originally Posted by JDC View Post
    Hi All,

    I recently let my pool guy go and I'm in the process of balancing the water. First I found that the TA is low (40ppm) so I'm addressing that by adding baking soda. Our pool has always needed to add MA to combat high PH, and I think I just discovered why...

    Next I noticed that I had absolutely no CYA as we have a SWC and our pool guy obviously didn't think we needed it. I am addressing that by adding CYA.
    You do NOT want to raise your TA if your pH tends to rise over time. Keep your TA low. You will use far less acid as a result. What you should use for additional pH buffering is 50 ppm Borates (say, from boric acid from DudaDiesel or The Chemistry Store or from a combination of 20 Mule Team Borax and Muriatic Acid added separately). Have you read the Pool School article Water Balance for SWGs?

    Basically, TA is a SOURCE of rising pH so if the pH tends to rise over time you do NOT want to raise the TA. The borates buffer the pH without being a source of rising pH themselves. Basically, TA is mostly a measure of the bicarbonate in the water and carbonates include carbon dioxide that outgases from the water causing the pH to rise. Pools are essentially over-carbonated, but with your high CH you have no need for such a "normal" TA range. Note that even in the Pool School Recommended Levels the TA range for SWG pools is lower at 60-80 than for non-SWG pools. However, that chart assumes you have your CH lower than you do so in your case you need to compensate by having your TA be lower. You can also have a higher pH target of around 7.7 to 7.8 and don't try and lower the pH below 7.5 whenever you add acid.

    So you should first add CYA to your pool since that will protect chlorine breakdown from sunlight and let your SWG not work as hard. With your SWG not having to be on as long, that will reduce the rate of pH rise due to the SWG aerating the water with hydrogen gas bubbles (and reduces any undissolved chlorine gas outgassing). Assuming a starting point of a pH of 7.8, TA of 40 ppm, no CYA, and CH of 800 ppm, then you could add the following per 10,000 gallons (you didn't give your pool water volume nor the pool water temperature).

    6.7 pounds of CYA to increase it from 0 ppm to 80 ppm -- this will lower the pH since CYA is acidic
    36.8 pounds of 20 Mule Team Borax to raise borates from 0 to 50 ppm -- this will also raise the pH, but split this dosage into four parts and alternate with the Muriatic Acid
    25.6 cups of Muriatic Acid (31.45% Hydrochloric Acid) -- this balances against the Borax -- this should be split in dosage into four parts alternating with the Borax

    You will then end up with a pH of 7.7, TA of 75, CYA of 80 ppm, CH of 800 ppm. If you need/want to lower the TA further to around 60 ppm then you would add more Muriatic Acid and aerate the water though you could just add acid over time and the TA should slowly drop.
    16,000 gallon outdoor in-ground 16'x32' plaster pool; Pentair Intelliflo VF pump; Pentair IntelliTouch i9+3s control system; Jandy CL-340 square foot cartridge filter
    12 Fafco solar panels; Purex Triton PowerMax 250 natural gas heater (200,000 BTU/hr output); automatic electric pool safety cover; 4-wheel pressure-side "The Pool Cleaner"

  12. Back To Top    #12

    Join Date
    Mar 2007
    Location
    San Rafael, CA USA
    Posts
    12,082

    Re: Idea to reduce calcium hardness

    Quote Originally Posted by bdex View Post
    I have the same issue with CH. And I also have SWG pool. I actually get little white flakes on the bottom of the pool that tend to accumulate in the corners. This just started to get bad last year. I have the wife vacuum to waste, I backwash and rinse often (maybe more often than necessary) and the issue has seemed to resolve itself. Mainly due to the drain and refill that happens when I need to add water. I also had an outside spigot ran that runs thru my water softener in the house. It is right by the pool for this purpose. We shall see when I reopen in the spring.
    If you are getting lots of flakes from your salt cell then your water is not in proper balance. Your saturation index (combination of pH, TA and CH in particular) is too high and you probably need to lower your TA level especially given your high CH. Do you use 50 ppm Borates? If not, then adding 50 ppm Borates would significantly cut down the amount of calcium carbonate scale/flakes from the salt cell because it cuts down the amount of pH rise roughly in half in the cell.
    16,000 gallon outdoor in-ground 16'x32' plaster pool; Pentair Intelliflo VF pump; Pentair IntelliTouch i9+3s control system; Jandy CL-340 square foot cartridge filter
    12 Fafco solar panels; Purex Triton PowerMax 250 natural gas heater (200,000 BTU/hr output); automatic electric pool safety cover; 4-wheel pressure-side "The Pool Cleaner"

  13. Back To Top    #13

    TFP Guide

    chiefwej's Avatar
    Join Date
    Jun 2011
    Location
    Tucson
    Posts
    2,853

    Re: Idea to reduce calcium hardness

    You can hook you auto refill to your water softner and that way you aren't continua adding even more calcium to the pool.
    chiefwej
    Tucson, AZ
    16x36 rectangular (19k) Pebble Tec play pool/spa, Pentair Intelliflo VS 011018, Super II 2hp (spa), Aqua Rite T-15 SWG, Pro Grid 60 DE, Hayward H400 & Heliocol Solar heating, A&A infloor system, fill water w/high CH and TA, 50 ppm borates,TF-100 test kit

  14. Back To Top    #14

    Join Date
    Jan 2015
    Location
    Carlsbad, CA
    Posts
    6

    Re: Idea to reduce calcium hardness

    Thanks chemgeek! My pool is about 12 or 13k gal and current temp is 56

    As of this morning here is what I have
    FC 5
    PH 7.8
    TA 80
    Cya 30
    CH 800
    I haven't read the SWG article but I will now! And also going to get some borax.
    Thanks for your help!
    12K gal in ground oblong concrete pool & spa built 2012, pentair equipment, DE filter

  15. Back To Top    #15

    Join Date
    Sep 2013
    Location
    Dallas-Ft. Worth Metroplex, TX
    Posts
    810

    Re: Idea to reduce calcium hardness

    Quote Originally Posted by chiefwej View Post
    You can hook you auto refill to your water softner and that way you aren't continua adding even more calcium to the pool.
    Would that not add too much salt to the pool?
    14K Freeform Gunite w/60% Blue Quartz plaster, Quad DE filter, Intelliflo VS Pump + Booster for Cleaner, Aquacal Heat Pump

  16. Back To Top    #16
    Richard320's Avatar
    Join Date
    Jan 2010
    Location
    San Dimas, CA (LA County)
    Posts
    18,768

    Re: Idea to reduce calcium hardness

    Quote Originally Posted by JDC View Post
    Thanks chemgeek! My pool is about 12 or 13k gal and current temp is 56

    As of this morning here is what I have
    FC 5
    PH 7.8
    TA 80
    Cya 30
    CH 800
    I haven't read the SWG article but I will now! And also going to get some borax.
    Thanks for your help!
    Hang on a second...

    Were you planning to lower the CH? I would recommend doing that first. My experience: CH rises about 25 per week during the summer due to evaporation and refill. So you WILL have to do something about it this year. My advice is to replace any water you plan to replace before you start dumping Borax or any other chemical in. Otherwise, it will just end up going down the drain when you do deal with the CH. And there's more to adding Borax than just dumping it in. It will drive the pH up, and you'll need to add acid to counter that. More expense to pump down the drain when you are forced to lower CH.
    16K freeform gunite with spa; Pentair 4000 DE filter; Century Whisperflow 1 HP; Pentair Minimax heater.
    Troublefree does not mean Maintenancefree. It's like brushing your teeth: You can spend a couple minutes a day and pennies a week or go to the dentist once a year and spend several thousand dollars.
    A pool is like a pet - you have to feed it every day, even the days you don't want to play with it!

  17. Back To Top    #17

    Join Date
    Mar 2007
    Location
    San Rafael, CA USA
    Posts
    12,082

    Re: Idea to reduce calcium hardness

    Richard is correct. If you intended to lower your CH via water dilution or reverse osmosis then that should be done first since it will lower ALL the water parameters. So there's no sense in getting the CYA or Borates up higher if you are going to dilute the water to get the CH down. What I wrote was assuming you were keeping things where they are and needed to balance more against the pH rise. It's still valid advice, but should be deferred until after you do anything to lower the CH, if that's what you do. In other words, the sequence of steps is important.
    16,000 gallon outdoor in-ground 16'x32' plaster pool; Pentair Intelliflo VF pump; Pentair IntelliTouch i9+3s control system; Jandy CL-340 square foot cartridge filter
    12 Fafco solar panels; Purex Triton PowerMax 250 natural gas heater (200,000 BTU/hr output); automatic electric pool safety cover; 4-wheel pressure-side "The Pool Cleaner"

  18. Back To Top    #18

    Join Date
    Jan 2015
    Location
    Carlsbad, CA
    Posts
    6

    Re: Idea to reduce calcium hardness

    ok thanks I think I would like to get the CH back to recommended levels and the I'll balance everything out as per the SWG recommendations. Thanks a ton for taking the time to help!
    12K gal in ground oblong concrete pool & spa built 2012, pentair equipment, DE filter

  19. Back To Top    #19
    Patrick_B's Avatar
    Join Date
    Jun 2011
    Location
    Midland TX
    Posts
    15,001

    Re: Idea to reduce calcium hardness

    Quote Originally Posted by zethacat View Post
    Would that not add too much salt to the pool?
    No it will not. But, most softeners made for residential use are not big enough in practical terms
    to keep up with pool makeup demands. Generally speaking, this will normally be the case.
    TFP Moderator
    Essential Links:
    ABC's Of Pool Chemistry, Test Kits, SLAM Your Pool
    28K Gal IG FreeForm, CLI Quartz, Pentair 36"SF & VS Pump, Dolphin M5, Rheem

  20. Back To Top    #20

    TFP Guide

    chiefwej's Avatar
    Join Date
    Jun 2011
    Location
    Tucson
    Posts
    2,853

    Re: Idea to reduce calcium hardness

    Quote Originally Posted by Brushpup View Post
    No it will not. But, most softeners made for residential use are not big enough in practical terms
    to keep up with pool makeup demands. Generally speaking, this will normally be the case.
    By my calculations, a 1/2 drop in my 16 x 36 pool only equates to approximately 150 gallons. I don't think my water softner will be overwhelmed. Even at twice that level of evaporation (which we can have here in the desert), 300 gallons per day extra water use wouldn't be a huge problem for the water softner.

    Trying to fill a pool with softened water would be an entirely different matter.
    chiefwej
    Tucson, AZ
    16x36 rectangular (19k) Pebble Tec play pool/spa, Pentair Intelliflo VS 011018, Super II 2hp (spa), Aqua Rite T-15 SWG, Pro Grid 60 DE, Hayward H400 & Heliocol Solar heating, A&A infloor system, fill water w/high CH and TA, 50 ppm borates,TF-100 test kit

Page 1 of 2 12 LastLast

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •