My Pool Turned Green Lots Last Summer after Hard Rain. What should I do?

Last year the pool turned green a couple of times after a hard rain. Anything I can do to prevent this?  Also other pool owners have told me that they shock their pool once a week should I be doing that?

 

Vinyl Liner Pool Opening Series Green Water (4)
This is algae growing on the bottom of the pool. Shock and Vacuum!

Yes, shocking the pool once a week is great. You can add 1-2 gallons of liquid chlorine and that will do the trick. Just do it when you know no one will be using the pool for about 24 hours. There are also non chlorine shock available that you can swim right after. I just use liquid in my pool.

For your main sanitizer do you have chlorine tablets in a floater in the pool? You should either do that, or add a chlorinator at the equipment pad that will release a consistent amount of chlorine into the pool to maintain a level of 1-3ppm at all times. Any pool store should have a floating dispenser and 1″ or 3″ tablets you can put in. There is also a chlorinator we can add to the equipment pad that will put the chlorine in after the heater.

algae green pool
Bright Green = high pH/high Alkalinity

You can also buy a bottle of algaecide and add about 4 ounces a week to help prevent algae.

The other reason a pool can turn green is if the pH is off. Murky green is typically pH too low, flourescent green is when pH is too high. Some green also indicates algae, but if it’s only happening after rain, it’s probably pH. When pH is off it often affects swimmers skin. Itchy or residue after getting out of the pool depending on which it is.

Vinyl Liner Pool Opening Series Green Water (7)
Dull Green – problem = low pH/low Alkalinity

If you buy some test strips from a local pool store you can test it at home and it will tell you what your levels are. You can also bring a sample of your water in to a pool store and they can run a complete diagnostic test for you. We suggest you do that once a month during the summer.