I've got a similar problem and thinking now it's from the fill water. The only area in the pool where I have stains is where I put the hose into the pool...

I've done the Vitamin C test...It worked! Now what? I've read some threads from Marie, but getting conflicting information from my pool store.

Now they've sold me a Stain Test Kit to specifically identify what the stain is. I haven't used it yet since I already know that it's metal stain.

So here are some questions...

Pool Manufacturer's User Manual suggests using jack's Magic Pink or Metal Magic as a preventative, BUT how do I get rid of these stains to begin with?

Pool store suggested rubbing Jack's Magic Pink on the stains in a sock. the stained area is too big to rub with a sock IMHO. Is there something I can put into the water that will remove the stains or will I be forced to rub the stains directly for best results???

Salt Water Pool. Ph 7.4; TA 120 Cya: 22ppm

Thanks