Calcium Hypochlorite Granules 68% - Powerful Pool Shock Treatment, Algae & Bacteria Control, Sanitizer for Swimming Pools, Spas & Hot Tubs - 25 LB

Works perfectly. Price is more reasonable than local pool supply venders. Free amazon shipping makes this product more competitive than larger tubs of shock. 2lbs brings my 26,000 gallon pool up to 20PPM. VERY GOOD PRODUCT that keeps algae and water cloudiness under good control.

I've been using this just as I was previous brand & keeping water crystal clear. That plus great bucket though hard to open best price of all others. I'll buy again

Worst packaging design ever engineered. Lid is impossible to open properly. I had to cut the top off with a power tool. Ridiculous design do not buy this unless you want to be very frustrated

I use this to treat my rainwater collection barrels at a very low dosage. We use the water for showering and doing dishes

High quality at a good price. That's hard to find for your pool nowadays.

Does the job

The lid on this thing is impossible to open properly. You can see it was intended to have one of those tear off seals around the lip, only there place where starting pull tab is molded into the plastic. Even after using a pair of snips to separate it, and then pulling it off, the lid still wouldn't come open. I tried using a screw driver to get under the lip and pry it, but that wasn't even working. I eventually just punched a hole in the lid and used the snips to cut it apart.Will not buy again. Even though it was the cheapest option, I'll pay a little more for something that's less of a pain to deal with.

Affordable