Quote Originally Posted by errodr27
Hello,

I have a 20x40 IG vinyl pool. I have been shocking weekly using 3lbs. of power powder plus.

Is this excessive? How often should I shock the pool?

Thanks...

I'm pretty new to this forum myself -- these people have helped me out greatly -- so I'm trying to help "pay forward" -- here are some tips that might be helpful for you:

#1 - Read the "stickies" at the top of the forums. I've copied [B]Ben's Best Guess Chart[B] for you below-- hope that helps.

#2 - Get a DROP-BASED kit (or order Ben's kit -- it's great -- site may be down right now so you'll have to check) and then POST SOME NUMBERS:

FC -
CC-
TC-
pH -
Total Alk -
CYA -
Cal -
Salt-

If you post your numbers, you'll probably get a lot more responses. I think there's also a sticky titled: Beginner's Guide to Pool Chemistry Needs. (If you're like me -- I have to read and RE-read everything! LOL)

Happy swimming!
Exclamation Best Guess CYA chart
Ben's 'best guess' FC/Stabilizer table for algae free operation of OUTDOOR pools -- as of July 2003 --

Use the info in this chart to help you figure out what levels of chlorine you need to maintain in your pool based on the amount of CYA (cyanuric acid, also called stabilizer) that you have in your pool. (FC = free chlorine)

Stabilizer . . . . . . Min. FC . . . . Max FC . . . 'Shock' FC
=> 0 ppm . . . . . . . 1 ppm . . . . . 3 ppm . . . . 10 ppm
=> 10 - 20 ppm . . . . 2 ppm . . . . . 5 ppm . . . . 12 ppm
=> 30 - 50 ppm . . . . 3 ppm . . . . . 6 ppm . . . . 15 ppm
=> 60 - 90 ppm . . . . 5 ppm . . . . . 10 ppm . . .. 20 ppm
=> 100 - 200 ppm . . . 8 ppm . . . . . 15 ppm . . .. 25 ppm