WATER CHEMISTRY CALCULATORS


CALCULATE POOL VOLUME
Pool Shapes
SELECT SHAPE OF POOL:
LENGTH: ' "
WIDTH: ' "
AVERAGE DEPTH: ' "    Average depth = shallow end depth + deep end depth / 2.
Significant Figures:                       
CALCULATED RESULTS
Your pool volume is
The complex shapes of some pools would have to be broken down into several shapes to estimate pool volume.





CALCULATE HOW MUCH WATER IT TAKES TO FILL THE POOL
GALLONS OF WATER IN POOL WHEN FULL:  gallons (US)
AVERAGE DEPTH OF POOL WHEN FULL: ' "
INCHES OF FILL WATER ADDED TO POOL:  inches

    
CALCULATED RESULTS
At  gallons per inch, you used  gallons of fill water and started with gallons in the pool. 
This calculator will calculate how much water it takes to fill your pool and how many gallons are in a certain depth of water.

1. Enter the gallons of water in the pool when its full.
2. Enter the average depth of pool when its full in inches. If you have a bowl shape or one end is deeper than the other, take several measurements to get the average depth.
3. Enter the inches of fill water added to the pool.
4. Click calculate.





CALCULATE CHEMICAL LEVELS FROM EVAPORATION AND REFILLING
GALLONS IN POOL BEFORE EVAPORATION OR WHEN FULL:  gallons (US)
GALLONS OF FILL WATER ADDED TO POOL TO REPLACE EVAPORATION:        gallons (US)
  POOL WATER TEST RESULTS FILL WATER TEST RESULTS CALCULATED RESULTS
CH:  ppm  ppm  ppm
TA:  ppm  ppm  ppm
      
Evaporation will lower the water level leaving things behind such as CH. This will make the chemical levels more concentrated than when full. If you refill with 0 ppm of fill water then the level would return to where it started from but if you add fill water that has any of the chemical in it, it will cause the level to keep increasing.

The one most people have to be concerned about is Calcium Hardness since it can only be lowered by draining and refilling with a lower level amount of fill water or by reverse osmosis which is not really cost effective. If the fill water contains a high amount of CH to start with then this makes matters worse.

If the fill water has a high TA level and there is alot of evaporation such as in the summer when there is no rain to replenish the evaporation then the TA level can start to rise along with the CH from having to add fill water every day or two. The TA level is fairly easy to lower so this is not much of a concern.

As for CYA, Salt and Borates, these things shouldn't be in fill water. City fill water will usually have some FC but since FC is always being consumed there is no need to calculate for it.





CALCULATE CHEMICAL LEVELS AFTER MIXING TWO BODIES OF WATER
GALLONS OF WATER IN POOL:  gallons (US)
GALLONS OF FILL WATER ADDED TO POOL:        gallons (US)
  POOL WATER TEST RESULTS FILL WATER TEST RESULTS CALCULATED RESULTS
FC:  ppm  ppm  ppm
TA:  ppm  ppm  ppm
CH:  ppm  ppm  ppm
CYA:  ppm  ppm  ppm
SALT:  ppm  ppm  ppm
BORATES:  ppm  ppm  ppm
TEMP:      
      
This calculator will calculate what the chemical levels will be after mixing two bodies of water such as filling the pool upon opening or calculating what will happen with large amounts of rain water. For this calculation you would test both bodies of water before they mix. If calculating rain water, the fill water test results will all be 0 except for the temp.

1. Enter the gallons of water that are in the pool.
2. Enter the gallons of fill water you are going to add to the pool.
3. Enter the test results of the pool water and fill water.
4. Click calculate.

Note: This calculator does not calculate for evaporation. Use the other calculator for that.





CALCULATE THE % OF FC LOST IN A DAY
Day 1: ppm FC Day 2: ppm FC
    
CALCULATED RESULTS
% daily FC loss.
1. Only add chlorine before or after the testing and not during. Allow the chlorine to thoroughly mix before testing.
2. Test the FC level.
3. The next day at the same time, test again, then calculate your results above.

The higher the FC level to start with, the better the accuracy.
Test on different days with different weather conditions, ex: sunny vs cloudy weather.
This can be done as many times as you wish to ensure accuracy.
If you have algae, then the FC loss is not going to be accurate until the algae is gone.
If your CYA level changes, then the daily FC loss will likely change with it. Small changes aren't going to matter much.





ESTIMATE DAILY FC LOSS
CYA LEVEL: ppm

% Daily FC Loss
STARTING FC LEVEL: ppm
AMOUNT OF FC ADDED EACH DAY: ppm
Show Daily FC Additions           Significant Figures:                    
CALCULATED RESULTS
Day 1: FC dropped to ppm, raised back to ppm Day 8: FC dropped to   ppm, raised back to ppm
Day 2: FC dropped to ppm, raised back to ppm Day 9: FC dropped to   ppm, raised back to ppm
Day 3: FC dropped to ppm, raised back to ppm Day 10: FC dropped to ppm, raised back to ppm
Day 4: FC dropped to ppm, raised back to ppm Day 11: FC dropped to ppm, raised back to ppm
Day 5: FC dropped to ppm, raised back to ppm Day 12: FC dropped to ppm, raised back to ppm
Day 6: FC dropped to ppm, raised back to ppm Day 13: FC dropped to ppm, raised back to ppm
Day 7: FC dropped to ppm, raised back to ppm Day 14: FC dropped to ppm, raised back to ppm
This calculator helps to estimate your FC loss over time such as when going on vacation. The daily drop in FC can vary depending on sunlight, organics, swimmers, water temperature, time of year and other factors.

1. Select your CYA level. A percentage of daily FC loss and recommended FC levels will be shown for that CYA level. Indoor pools will loose much less FC.
2. After selecting your CYA level, the daily FC loss percentage can be changed to the amount of FC that is actually lost per day or an average amount.
3. For the most accuracy, test your pool to see how much FC it looses in a day. Use the "CALCULATE THE % OF FC LOST IN A DAY" calculator above.
4. Enter your starting FC level. Many people will raise the FC to shock level when starting. Do not go over mustard algae shock level.
5. Enter the amount of FC you plan to have added every day.
6. If you plan on adding FC every other day or something other than every day, click "show daily FC additions" and input the days separately.
7. Click "calculate" to estimate your daily FC levels. Day 1 would be the first day of leaving the pool unattended and so forth.

** That CYA level is not recommended for that type of pool.

COLOR KEY: FC too high, FC good for non-swg and swg pools, FC good for swg pools, FC too low





DECODE THE BLEACH OR LIQUID CHLORINE MANUFACTURING DATE
SELECT PRODUCT:
SAMPLE OF MANUFACTURING CODE: Year Day
ENTER THE YEAR IT WAS MADE:
ENTER THE DAY IT WAS MADE:
         
CALCULATED RESULTS
Made on:
This calculator automatically figures for a leap year so make sure the year is correct.

Bleach or liquid chlorine looses strength over time so you want to know how old your stock is. You will want to store your liquid chlorine in a cool dark place. The higher the strength of the chlorine, the faster it decomposes as noted in the table below.


  Half-Life In Days
Concentration 90F 85F 80F 75F
20% 22.4 31.8 51.2 69.2
15% 48 68 100 148
10% 115 164 241 357
5% 371 527 735 1147





SALT WATER GENERATOR OUTPUT
GALLONS OF WATER IN POOL: gallons (US)
SWG CHLORINE OUTPUT SPECIFICATION: lbs per day
         
CALCULATED RESULTS
The SWG unit is capable of producing ppm of FC per day or ppm of FC per hour in a pool this size.





CALCIUM PHOSPHATE SCALING
PH:
CH: ppm
PHOSPHATES: ppm or ppb
WATER TEMP: F
                                  
 
 
This calculator only gives an idea of when calcium phospate scaling may start to occur. This does not mean calcium phosphate scaling will occur just above this level and it might not occur until some amount of over-saturation, which could be higher than what is shown here.

The pH in a SWG hydrogen gas generation plate is around 8.5, higher than what the pool water is, so you may want to use a pH of 8.5 if you have a SWG to avoid scaling inside the unit.

Regular calcium carbonate scale will bubble with muriatic acid and calcium phosphate will not. Try a drop of acid on the scale if you suspect you have calcium phosphate scale.



16.11.24
2016 J Fredrick H