Become a TFP Supporter Pool Math Forum Rules Pool School
Results 1 to 8 of 8

Thread: Pool Math question. How much Calcium Chloride to add to bring up CH?

  1. Back To Top    #1

    Join Date
    Oct 2015
    Location
    Kailua, Hawaii
    Posts
    24

    Pool Math question. How much Calcium Chloride to add to bring up CH?

    If you google this question or if you look at the instructions for some calcium chloride packages you will get the standard answer that seems most common, which is about 1.25 lbs to raise 10 ppm in 10,000 gallons. Some other sources say 1 - 1.25 lbs to raise 10 in 10k. Pool Math http://www.troublefreepool.com/calc.html says exactly 15 oz to raise 10 in 10k. Why the difference? Does it depend on other factors or what kind of cal-chlor you buy?
    20x35 IG pool "tiled" ~35,000 gallons; 500# Purex Triton II sand filter; Leap Pump (spectralight brand) variable speed pump; 40 year old pool (tiled 16 years ago); Taylor 2006; solar-breeze floating skimmer (currently down), Dolphin Nautilus Robotic Pool Cleaner (used 2-3 times per month), occasional manual vacuum to waste.

  2. Back To Top    #2
    Mod Squad jblizzle's Avatar
    Join Date
    May 2010
    Location
    Tucson, AZ
    Posts
    37,389

    Re: Pool Math question. How much Calcium Chloride to add to bring up CH?

    You missed that PoolMath also says:
    or add 20 oz by weight or by 23 oz volume of calcium chloride dihydrate.
    which matches what your google-foo returned

    Depends if you get calcium chloride OR calcium chloride dihydrate
    Jason, TFP Moderator
    18k IG pebblesheen pool, Hayward ProLogic P4 w/ T-15 SWG, Pentair 1HP 2-speed Superflo, Hayward 6020 DE filter
    500 sqft Heliocol solar panels, ThePoolCleaner, TF-100 test kit w/ SpeedStir
    Pool School + Test Kit + PoolMath = A TROUBLE FREE POOL
    If you found TFP helpful and we saved you money ... Become a TFP Supporter!

  3. Back To Top    #3

    Join Date
    Oct 2015
    Location
    Kailua, Hawaii
    Posts
    24

    Re: Pool Math question. How much Calcium Chloride to add to bring up CH?

    Hmmm....I see that, but now I'm actually more confused. Most of what I've seen that quotes the standard 1.25lbs to raise 10ppm in 10k mentions calcium chloride, or hardness increaser, but do not specifically mention "dihydrate." For example, this guy HOW TO RAISE CALCIUM HARDNESS IN A SWIMMING POOL - YouTube (I sometimes watch his videos, seems pretty grounded) uses that same formula and states calcium chloride but does not mention "make sure you get dihydrate." This seems to be standard advice, not just with this guy but around the internet.

    For example, this product is pretty typical for what you find Amazon.com : Pool Mate 1-2825 Calcium Increaser for Swimming Pools, 25-Pound : Patio, Lawn Garden. It recommends 1.25 for 10 in 10 and state on the box/package "calcium chloride" is the active ingredient, but does not mention dihydrate as far as I can see. Is it that just about every form of calcium chloride bought at a retail store or a pool supply store WILL be dihydrate even if it does not mention it on the package?
    20x35 IG pool "tiled" ~35,000 gallons; 500# Purex Triton II sand filter; Leap Pump (spectralight brand) variable speed pump; 40 year old pool (tiled 16 years ago); Taylor 2006; solar-breeze floating skimmer (currently down), Dolphin Nautilus Robotic Pool Cleaner (used 2-3 times per month), occasional manual vacuum to waste.

  4. Back To Top    #4

    Join Date
    Aug 2010
    Location
    Dallas, TX
    Posts
    4,052

    Re: Pool Math question. How much Calcium Chloride to add to bring up CH?

    I posted this elsewhere but got no answer. I'll ask here to keep the CH question together.

    I need 50-60 lbs of calcium chloride. Does this look like the right thing? This is about 1/4 the cost at Leslies.

    Snow Joe 50 lb. Re-Sealable Bag Calcium Chloride Crystals Ice Melter-MELT50CC - The Home Depot

    Or this, which is flakes...
    Vaporizer 50 lb. Calcium Flake Ice Melt Bag-VP-CF50BG - The Home Depot

    This one is a lot more, but they mention using it in pools
    Amazon.com : North American Salt 50850 Extreme 7300 Calcium Chloride Ice Melter, 50-Pound : Snow And Ice Melting Products : Patio, Lawn Garden

    Or any of them?
    Built in 1957 44,000 gallon in-ground, Wet Edge Primera Stone in Sky Blue, Intelliflo VF Pump, 600 lb. Pentair Triton II TR-100 Sand Filter, CircuPool RG 60 Plus SWG, TF-100 test kit
    If TFP has helped you, please click to SUPPORT TFP!

  5. Back To Top    #5

    Join Date
    Oct 2015
    Location
    Katy/Texas
    Posts
    411

    Re: Pool Math question. How much Calcium Chloride to add to bring up CH?

    Beware Buying the snowmelt products. I tried that and it turned out to actually be sodium chloride. I'm not saying that all of the snowmelt products are mislabeled, but some are. Amazon refunded my money and removed the suspect product from sale. I just had 25lb bucket of pool calcium delivered by by Amazon for $37.
    In ground, 14,000 gallon, white plaster, unheated, stone waterfall, DE Filter, Rainbow 320 Cl, Polaris 3900, FloVis flow meter, F100 test kit, Circupool RJ30+ SWG, Circupool VJ1/Speck Badu EcoM3V variable speed pump.

  6. Back To Top    #6
    borjis's Avatar
    Join Date
    Aug 2014
    Location
    Pacific NW
    Posts
    2,050

    Re: Pool Math question. How much Calcium Chloride to add to bring up CH?

    And you might consider a local pool store, just for the calcium.

    That's what I do. Only thing I buy there, sometimes I pretend to be looking at pumps if a
    customer is talking to the pool store employees (just for fun to see what advice they give)

    The one I go to has 25lb bucket for $ 37, so same as Amazon without any shipment wait time.
    16x32 IG Vinyl, 13,000 Gals. Hayward S-244T sand filter, SP2810X15 pump
    (1.5 HP motor) Raypak PR266AEN (266k btu) gas heater. TF-100 Test Kit.
    Dolphin E10 Cleaning Robot.

  7. Back To Top    #7

    Join Date
    Mar 2015
    Location
    Georgia
    Posts
    157

    Re: Pool Math question. How much Calcium Chloride to add to bring up CH?

    The "Pool" Calcium Hardness Increaser products are mostly if not all calcium chloride anhydrous. You would use calcium chloride in Pool Math. For the snow melt products like Peladow, you would use calcium chloride dihydrate in Pool Math. Some if not all the snow melt products are anhydrous, but they are a lower percentage (I recall 77% or so) of calcium chloride so the dihydrate section in Pool Math calculates correctly.
    16k AG Vinyl Sand Filter

  8. Back To Top    #8

    Join Date
    Aug 2010
    Location
    Dallas, TX
    Posts
    4,052

    Re: Pool Math question. How much Calcium Chloride to add to bring up CH?

    Leslie's is all I have, but I can go to the Commercial store tomorrow. They usually cut me a deal because I buy so much at once to maintain a 44k gallon pool. And, it's less than a mile away. Thanks for the help!
    Built in 1957 44,000 gallon in-ground, Wet Edge Primera Stone in Sky Blue, Intelliflo VF Pump, 600 lb. Pentair Triton II TR-100 Sand Filter, CircuPool RG 60 Plus SWG, TF-100 test kit
    If TFP has helped you, please click to SUPPORT TFP!

Posting Permissions

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