https://www.costco.com/chlorine-free-sun-shock-pool-purifier.product.100228627.html

[charitap]

Is this worth buying? I see a lot of good reviews and few issues with screw as well.
My pool is getting green in just 4 or 5 days. after shock.

 

[mknauss]

No.
What is your pool water chemistry? Do an Overnight Chlorine Loss Test

 

[joshuaj1975]

Looks like a plaster killer

 

[aztodd]

Is this worth buying? I see a lot of good reviews and few issues with screw as well.
My pool is getting green in just 4 or 5 days. after shock.

Many years ago before I found TFP I tried this product. It didn't help and was a huge pain to clean. Don't waste your time with it.

If you follow the guidance from this site, you'll never deal with algae again and spend way less time taking care of your pool.