Added about 3" of water to the pool and then we shocked and let circulate for a half hour, then tested FC. Had to add 3 big dippers to get it to turn pink with the 10 ml sample. I stopped adding drops at 40 it was still a strong pink color. I won't add any more tabs to the pool the supply house says "yes of course they have stabilizer in them". And we are using 10% liquid chlorine from the pool supply . Thanks for the help with everything. Will check back a bit later.