swimming pool , what is the most cost effective way to chlorinate a pool ? Powder , liquid ,tablets , other ?

Answer 1

The most cost effective way in the long term is actually using what's called a salt water chlorine generator. These units are pricey to begin with but pay off with the chemical savings later.
As to everything else that you've mentioned.
You need two types of chlorine to run a pool.
1/ Shock- This can be in a powdered form or liquid chlorine. Shock is just a fancy term for getting your chlorine levels high in a hurry to knock out organics and then the levels drop quite fast. You don't swim in this stuff until it's level has dropped. You're an organic.
2/ Sanitizer- The pucks. Low dose, constant input chlorine. Knocks out most, but not all of the organics. This you do swim in, if it's not accidentally turned up high. You can also use liquid chlorine if you have a pump type chlorinator such as the Chloromatic. It pumps in small doses of liquid at timed intervals.
What shock is better? They all have pros and cons. Liquid is cheap, granules aren't. Liquid has a high pH (raises the pH of your water which you have to counter with other chemicals which cost money). Liquid is hard to transport around, granules aren't. Liquid gets zapped out by ultra violet light from the sun a little quicker than granules. For granules, you really should pre mix it in water before adding to the pool, especially if the water is cold.
Pucks? Well, there are two types, primarily. Stabilized and non stabilezed. Stabilized contain small amounts of stabilizer to help keep the chlorine working in the pool instead of getting zapped by UV rays.