Purple Walls - Very High CYA

[Tom B2]

I've read some of the posts that relate to this issue. I've come to understand that I'll need to reduce the CYA through draining to get the level under control.

But, I have questions:

1) Will lowering the CYA cause the purple to disappear?
2) Assuming "NO" is the answer, what must I do to remove the purple? It does not seem to brush off. My pool is a one piece fiberglass, so draining it to scrub or clean the sides would not be an option.

I have a cartridge filter
It is a small pool ... 6 to 7k gallons
Foolishly have a tab automatic chlorinator, and so I will want to know of a Tab type that will not cause this CYA problem ... if such exists.

Thanks,
Tom

[muss08]

What is your current CYA level? Have you had your water tested for manganese? Purple problems often point to this.