Stains no quite coming out with Vitamin C, maybe not enought POP?

[waterbear]

I am going to assume you ordered the Jack's Magic stain kit. It is a good one and the products work but they are expensive. Some of their stain treatments can acutally take weeks to complete so you might also need a jumbo bottle of POP (Pool Owner Patience)! You never did reply if you tested the stain with a vitimen C tablet? If that cleared the stain where it sat then ascorbic acid WILL work. If it didn't then you might need oxalic acid or even more drastic measures.