When to replace cartridges?

[Pool Clown]

I pulled that out of my filter's instructions. 1:1 of 20% acid.

1:1 or 1 part water to 1 part acid is 50%

Or do you mean 1 part water to 1 part 20% acid?

Anyway, i use a product thats called filter blaster. And i've had REAL good luck with it.

2 cents...

 

[mas985]

I pulled that out of my filter's instructions. 1:1 of 20% acid.

Or do you mean 1 part water to 1 part 20% acid?

The instructions say 1:1 OF 20% acid. Or basically, a 10% acid solution.

 

[Pool Clown]

One of the things I noticed about the old ones was that they were causing the air filter to become clogged with these little white slivers of what I can only assume is the filter media, they look like white pine needles.

Corsair, If you're still out there, those white pine needles are probably your pool brush coming apart. Thats what they do when they sit in the sun for too long.