Hi, my pool was just replastered 2 weeks ago with Finest Finish commercial quartz in white. I am following the OnBalance bicarb startup procedure. The pool looks great and everything seems to be ok except for the following.
There is a black 1” spot on the bottom that I noticed a day or two after it was filled, see photo. There were several areas of exposed rebar after removal of the old plaster that were painted with black rustoleum, but a magnet isn’t drawn to the spot. Any ideas what this could be so early after completion? Should I try to remove it with a chlorine tablet or wait to do this until the plaster is fully cured? A few more smaller spots have appeared in the last few days, I don’t understand how white plaster can turn black especially so fast.
Second issue is PH balance. Every day I’m adding muriatic acid because the PH increases by .2 or .3, I guess this is normal but for how long? I’m measuring with an Apera PH60 and using the poolmath calculator. OnBalance has two different recommendations for PH, is either acceptable? The Bicarb startup post says to add acid to drop the PH to 7.6 when it reaches 8.0. OnBalance’s Poolhelp website says something different, which is to drop it to 7.7 to 7.9 when PH gets to 8.2 and be sure it stays below 8.2 for the first month. Thanks!
There is a black 1” spot on the bottom that I noticed a day or two after it was filled, see photo. There were several areas of exposed rebar after removal of the old plaster that were painted with black rustoleum, but a magnet isn’t drawn to the spot. Any ideas what this could be so early after completion? Should I try to remove it with a chlorine tablet or wait to do this until the plaster is fully cured? A few more smaller spots have appeared in the last few days, I don’t understand how white plaster can turn black especially so fast.
Second issue is PH balance. Every day I’m adding muriatic acid because the PH increases by .2 or .3, I guess this is normal but for how long? I’m measuring with an Apera PH60 and using the poolmath calculator. OnBalance has two different recommendations for PH, is either acceptable? The Bicarb startup post says to add acid to drop the PH to 7.6 when it reaches 8.0. OnBalance’s Poolhelp website says something different, which is to drop it to 7.7 to 7.9 when PH gets to 8.2 and be sure it stays below 8.2 for the first month. Thanks!
