PoolSoft ©

 By simply multiplying and dividing a few numbers you
 can calculate the exact chemical dosage for any size
 swimming pool or spa.

Alkalinity Cyanuric acid        Calcium

Chlorine   Persulfates          pH drop count

pH         Specialty Chemicals  Biguanide,Baquacil,Softswim

Dilution   Volume               Gallons,ozs,teaspoons

Alkalinity: US Weights
  Raise: ozs sodium bicarbonate = gals x ppm x .000224
  Lower: ozs sodium bisulfate =  gals x ppm x .00034
  Lower: ozs Muriatic 31% =  gals x ppm x .000256 

  Ex: To raise Alkalinity 10,000 gallons, 10ppm
      22.4 ozs sodium bicarbonate =  10000 x 10 x .000224 

Alkalinity: Metric weights
  Raise: grams sodium bicarbonate = liters x ppm x .00168
  Lower: grams sodium bisulfate =  liters x ppm x .00255 
  Lower: ml Muriatic 31% =  liters x ppm x .002

  Ex: To raise Alkalinity 1,000 liters, 10ppm
      16.8 grams =  1000 x 10 x .00168

Cyanuric: US weights
  Raise: ozs cyanuric acid = gals x ppm x .000128

Cyanuric: Metric weights
  Raise: grams cyanuric acid = liters x ppm x .00096

Calcium: US weights
  Raise: ozs calcium chloride = gals x ppm x .00016
  Raise: ozs calcium chloride dihydrate = gals x ppm x .0002

Calcium: Metric weights
  Raise: g calcium chloride = liters x ppm x .0012 
  Raise: g calcium chloride dihydrate = liters x ppm x .0015 

Chlorine: US weights:  % is available chlorine in compound, 65% = .65
 Raise: ozs chlorine = gals x ppm x .000128 / %

 Ex: To raise chlorine 10,000 gallons 1ppm
   1.97 ozs calcium hypochlorite (65%) = 10000 x 1 x .000128 / .65

Chlorine: Metric:  % is available chlorine in compound, 65% =.65
 Raise: 
  Solid:  grams chlorine (% available in) = liters x ppm x .00096 / %
  Liquid:  ml chlorine (% available in) = liters x ppm x .001 / %
  
  Ex: 1.47 g calcium hypochlorite (65%) = 1000 x 1 x .00096 / .65
      20.00 ml Bleach (5%) = 1000 x 1 x .001 / .05

Shocking with sodium persulfate or potassium peroxymonosulfate

  US weights:  ozs persulfate  = gals x .0016
  Metric weights: grams persulfate = liters x .012

pH: drop count dosages. US weights
  Raise: ozs sodium carbonate = gals x drops x amt per drop per gal
  Ex. to raise ph from 6.8 to 7.4 - 6 drops were required, 7,500 gals
     18 ozs sodium carbonate = 7500 x 6 x .0004 (#factor)

pH: drop count dosages. Metric weights
  Raise: grams sodium carbonate = liters x drops x amt per drop/liter
  Ex. to raise ph from 6.8 to 7.4 - 6 drops were required, 4,500 L
     81 grams sodium carbonate = 4500 x 6 x .003 (#factor)

  ** #factor - amount per drop per gallon or liter depends on test kit.
     If reducing pH use respective #factor  for bisulfate or muriatic.
     If alkalinity is low, any adjustment will dramically effect pH.
     Always re-test pH when ever any adjustments are made.

pH: If your not performing drop count test, use the following.
    Assumes alkalinity is not very low or very high   
  US weights:   
    Raise: .2: 7.0 t0 7.2  retest after each .2 adjustment
           ozs sodium carbonate = gals x .0008 
    Lower: .2: 7.8 to 7.6  retest after each .2 adjustment
           ozs sodium bisulfate = gals x .001 
           ozs muriatic acid 31% = gals x .0008 

  Metric weights:   
    Raise: .2: 7.0 t0 7.2  retest after each .2 adjustment
           grams sodium carbonate = liters x .006 
    Lower: .2: 7.8 to 7.6  retest after each .2 adjustment
           grams sodium bisulfate = liters x .0075 
           ml muriatic acid 31% = liters x .006 

Biguanide (Baquacil, SoftSwim): US weights
  Raise: ozs biguanide  = gals x ppm x .000128

Biguanide: Metric weights
  Raise: ml biguanide = liters x ppm x .001
---------------------------------------------------------------
Shocking with 27% hydrogen peroxide for Biguanide systems

  US weights:  ozs hydrogen peroxide = gals x .0128
  Metric weights: ml hydrogen peroxide = liters x .1

Miscellaneous, Specialty chemicals. 
Many chemicals are based on number of ozs (ml) per 
number of gallons (liters)
US weights: ozs = gals x (# of ozs) / (# of gallons)

Ex. If dosage is 16 ozs per 10,000. volume is 25,000 then 
    40 ozs = 25000 x 16 / 10000

Metric weights: ml = liters x (# of ml) / (# of liters)

Ex. If dosage is 100 ml per 10,000. volume is 75,000 then 
    750 ml = 75000 x 100 / 10000

1 gallon = 128 ozs
1 quart = 32 ozs
1 pint = 16 ozs
1 cup = 8 ozs
1 ozs = 2 tablespoons = 6 teaspoons

If some chemicals are to high, you may have to dilute the water
to reduce it. Calcium, cyanuric, TDS, etc.
Ex. If calcium is 400ppm and you want to reduce it to 200ppm.
      Source water (to add) is 100ppm
      PR = test reading of pool water, ppm
      SR = test reading of source water, ppm
      FR = final test reading you want to adjust to, ppm
           must be between SR and PR.
      PV = pool water volume
      SV = source volume to add
      %  = percentage of water you'll have to drain

      % (to drain) = (PR - FR) / (PR - SR)

      .67 = (400 - 200) / (400 - 100) 
      You'll need to drain 2/3 (67%) of the pool.
      
      % times pool volume, will give you the amount of 
      water you'll have to drain and source(new) water you'll 
      have to add.

  You can use this formula to also increase ppm of chemical.

US - Gallons and Feet
- Rectangular: Gallons = length x width x avg depth x 7.5
- Oval: Gallons = length x width x avg depth x 5.89
- Round: Gallons = diameter x diameter x avg depth  x 5.89

    1 cubic foot = 7.5 gallons: 1 cubic yard = 203 gallons
    1 cubic metre = 264 gallons:

METRIC - Liters and Meters;  1 cubic metre = 
- Rectangular: Liters = lengtht x width x avg depth x 1000
- Oval:  Liters = length x width x avg depth x 785
- Round: Liters  = diameter x diameter x avg depth x 785

** approx avg depth = shallow depth + deep depth / 2

** Oval pools tend to be rectangular with rounded ends.
    If this is the case Increase volume by 5-10% .

All of the above calculation formulas are automatically performed for you by the Software.

The calculation formulas, dosages and chemical concentrations
are based on the most generally accepted recommendations
at the time of it's writting. They may change over time.
Always follow the chemical manufacturers current label instructions.

Copyright 1992-2001 PoolSoft. All rights reserved.
Tim Sullivan, 35 Brewster Drive,  Gales Ferry, Connecticut,  USA
860-464-2217