Chlorine powder is essential to killing germs such as algae and bacteria that exist in your pool and multiply at very fast speeds
. To kill off these germs, you'll need to use a large amount of chlorine powder in your water. Depending on the size of your pool, you may need to use more powder than others. Chlorine powder can tend to be expensive, so you should always check just how much you'll need before you buy. This is the chemical you ought to have, as it's impossible to keep your pool free of germs without it. If you have already bought it or if you are planning to purchase a huge supply, you shouldn't worry as you'll always have the need for it - meaning that you can never buy enough chlorine powder.