How do you shock a 18x48 pool?

Answer 1

Studied some chemistry, am a NSPF certified pool and spa operator, I also managed the second largest pool in western Canada (by volume) for a summer...

To effectively shock a pool, the chlorine concentration must stay above 10parts per million (10ppm) for at least 10 hours @pH 7.2-7.4. Basically, this will kill any biological water-bourn contaminants, namely the [i]clostridium sp.[/i] of bacteria which is commonly found in diarrhea and can lead to gastroenteritis.

Keep in mind 2 things.

1- the effectiveness of chlorine is dependent on pH (Cl2 forms hypocholous [b]acid[/b] when in solution with water. Hopefully based on the word "acid" one can determine that pH will be a factor. You may need to add muriatic acid (HCl) to keep your pH from spiking with the additional chlorine (need to form a "buffer solution", so to speak).

2- hypochlorous acid is NOT photostable. UV light (ie - sunlight) will irradiate all of the chlorine from your solution. There are products available for outdoor pools to help chlorine bind with H2O, namely "cyaneric acid". This should be available at any store that stocks pool supplies (Canadian Tire, Wal-mart anywhere else with a "sports department, chemical supply companies and pool/spa suppliers).

Alright, I am assuming that your dimensions given are in feet. I will also assume a depth of 5 feet, as that seems to be standard for above ground pools.

One - I convert to metric (because I'm from Canada, eh, plus I can't do these calcs in SAE units...)

18ft x (0.3048m/ft) = 5.4864m

52ft x (0.3048m/ft) =15.8496m

5ft x (0.3048m/ft) = 1.5400m

Multiply our returns to give a volume

5.4864m x 15.8496m x 1.5400m = 133.9142m^3 (cubic metres)

Since 1m^3 = 1000L/m^3...

133.9142 x 1000 = 133914.2 L of H20.

If you need this measurement in US gallons...

133914.2 x 0.2641 gal/L = 35366.74 US gallons

Cool.

From here, things become a little bit grey. I can make another assumption of the chemical you are intending to use to spike, but if I'm wrong, I could be very wrong. CaCl2 is different that working with Cl2(gas), and bromine will require a conc. nearly double that which would be effective from chlorine.

If you can add more information, I can answer your question completely, HOWEVER, I believe with that volume, you should be able to use the packaging from your spike chemical to determine how much chemical to use.

Generally, the packaging will give a measurement along the lines of "to raise the Cl level by 1ppm in 10000L, add "X" grams/kilograms". You already know your volume, 133914L, so multiply "X" by 13.4 (assuming the given dosage is per 10000L), then multiply (13.4)x(X)x(#of ppm you want to increase by). This should give you a final mass of chemical to add into your solution.

Remember to always wear gloves, goggles and a mask when working with granular chlorine, and bare in mind your wind speed and direction (it will kill all of the plantings around your pool deck).

Answer 2

3 bags ,my pool system works with temperature.Salt system will only work when water is at 73F.