Hello TPFers, I'm a new pool owner just bit the bullet to renovate the inherited pool (safety covered for 3 years), new plaster and new fill water. This morning, just noticed a yellow stain (thick hair like) on the steps in shallow end, that could not be brushed off. I read on the forum and used a v-c pill (500mg ones, from Costco) directly on it, rubbed a little. The color seems faded a little but stain itself seems a little wider. Surface of the stain feels rougher than the plaster surrounding surface.
I'm waiting for my K2006 kit so no direct measurement numbers yet from myself, but I took my water to leslies last Sun and they did tested 0.3ppm Cu in it. Their results show i have low FC, low CYA (5), TA 108; PH 8, CH 150. Since then, I have been alternating with 56% Cal Hypo, LC and 4 pucks of Clorox for Chlorination. I added some MA (using the poolmath tool) trying to bring down the PH to 7.5 (based on their 8 reading and the fact that I used Cal Hypo which may raise PH a little). Other than that, nothing was added into the pool. Daily brush *2, and skimming with net. I did have some debris and small leaves one of two in the deeper end. I'm refraining adding CYA before my test kit arrives this Sat, and the fact that I may need to rely on some pucks for a week out-of-town early next month.
Sorry for sounding anxious, but does it sound like Iron/rust stain or others? Do I need to keep the VC on much longer?
Thanks a lot.

I'm waiting for my K2006 kit so no direct measurement numbers yet from myself, but I took my water to leslies last Sun and they did tested 0.3ppm Cu in it. Their results show i have low FC, low CYA (5), TA 108; PH 8, CH 150. Since then, I have been alternating with 56% Cal Hypo, LC and 4 pucks of Clorox for Chlorination. I added some MA (using the poolmath tool) trying to bring down the PH to 7.5 (based on their 8 reading and the fact that I used Cal Hypo which may raise PH a little). Other than that, nothing was added into the pool. Daily brush *2, and skimming with net. I did have some debris and small leaves one of two in the deeper end. I'm refraining adding CYA before my test kit arrives this Sat, and the fact that I may need to rely on some pucks for a week out-of-town early next month.
Sorry for sounding anxious, but does it sound like Iron/rust stain or others? Do I need to keep the VC on much longer?
Thanks a lot.
