Am I correct in thinking that adding Metal Sesquesterant before testing can cause FC levels to skyrocket? HEDP based? I am assuming that I let the Metal Sesquesterant 'wear out' because I have not added more water to the pool and this AM I had the Iron staining coming back, the filter was orange again, so I put in 1/2 quart of hth Metal Control. It is already clearing the water and I will vacuum shortly, but from my own experiments today it seems that the Metal Control is throwing off the Chlorine levels. If I am correct in this, how long should it take before I can get an accurate FC reading?
My test results from this AM are
FC 30 (definately 30)
CC 0 (this has been .5 for 2 weeks until now)
CYA 50 (This is up from 35)
PH 7.2 (all week steady)
TA 70 (all week steady)
I am also a little confused about how the sesquesterant works. Say there are tiny particles of rust floating around, does the sesquesterant resuspend those particles? Or is it the case that once they are out, they are just in the water and stay there unless removed by the filtering?
2000GPH Intex Pump Larger Filter
Hayward Aqua Critter Vac