Hi cans25,
I would hold off on raising the chlorine until you filter for a while. As long as you are getting the "sludge" out, you are removing the metals. If it is sludge, it is in a solid form so it can be removed. When the metals are in solution they cannot be removed, then you need a sequestering agent so that the metals don't "fall out" and stain the surface of the pool. Keep running the sump using the batting to filter until the water runs clear, or you remove as much of the metals as you can. Then you can balance the water.