Hello, I’m new to the forum and hoping for some suggestions on an issue we’re having.
Last season I noticed a couple of black streak in the shallow end and deep of the pool. They could not be brushed off and they don’t have any texture when touching them. This season the problem seem to spread. It’s noticeably worse in the shallow end. The spots appear to have a dark core and smear like appearance around the core. I also noticed one on the wall in the shallow end that’s much smaller than the ones in the photos.
We had an algae problem towards the end of last season that I treated with a couple of products and eventually killed off with Green Treat. However, the pool has been looking good all season except for the black streaks. We have a saltwater pool with chlorine generator. The pH runs on the higher side of normal and I routinely add acid once a week to drop the pH. I recently had the water tested and there were measurable phosphate levels. Could this be black algae? I also read in a thread about the cause coming from the underside of the liner and bacteria. The pool is 10 years old and it’s the original liner.
FC - 4
PH - 7.6
ALK - 110
CYA - 60
Salt - 3500
Last season I noticed a couple of black streak in the shallow end and deep of the pool. They could not be brushed off and they don’t have any texture when touching them. This season the problem seem to spread. It’s noticeably worse in the shallow end. The spots appear to have a dark core and smear like appearance around the core. I also noticed one on the wall in the shallow end that’s much smaller than the ones in the photos.
We had an algae problem towards the end of last season that I treated with a couple of products and eventually killed off with Green Treat. However, the pool has been looking good all season except for the black streaks. We have a saltwater pool with chlorine generator. The pH runs on the higher side of normal and I routinely add acid once a week to drop the pH. I recently had the water tested and there were measurable phosphate levels. Could this be black algae? I also read in a thread about the cause coming from the underside of the liner and bacteria. The pool is 10 years old and it’s the original liner.
FC - 4
PH - 7.6
ALK - 110
CYA - 60
Salt - 3500
