Should I keep slamming?

[Connie Bee]

I found this site last summer, and after years of relying on the pool store experts, converted to liquid chlorine. The results were dramatic and wonderful.
This year, I'm having a little trouble. We had drained the pool down pretty low over the winter, so there was zero chlorine in the water upon opening several weeks back. We filled with well water (as we always do), and I slammed (for the first time). Water looks great, tests great, but silty black organic matter continuously accumulates on the bottom of our flat-bottomed pool, necessitating frequent vacuuming. I assume the black matter is dead algae, so I started slamming again today. Am I doing the right thing?

Thanks for your thoughts/advice,
Connie

PS - This is the last season for our very old pool that has lots bumps and small wrinkles in the liner. But still.....we shouldn't have this dirt on the bottom!

 

[Connie Bee]

Here's a picture of the silty black organic matter.

 

[mknauss]

Good idea to SLAM.
Have you been able to keep your FC above minimum with your low CYA?

 

[Connie Bee]

Thanks for your reply.
There was only 1 day that I had FC go below minimum.
I added CYA before the second SLAM to get up to 30.
I am gun shy on CYA because of past experience with getting CYA too high. So I add a little at a time. Will add more after done SLAMMING.