Hi all. While I'm waiting on my TF-100 kit to arrive, I needed ask a question about backwashing.
Before finding TFP, and at the advice of 3 pool stores, we backwashed several times in June, after going through the process to kill the mustard algae (which STILL isn't dead). So now that we know how to do this right, I need to ask a couple of questions still.
#1: Is it necessary to b/w after doing the high fc kill, as well as vacuum to waste during the process?
#2: I wanted to lower our CYA to about 20-30 before starting the kill this time, so I don't have to use as much chlorine. But if we're going to be vacuuming to waste and backwashing afterward anyway, will another b/w and vac'g to waste during the kill lower my CYA too much? Or should I just leave things as they are and do the kill FIRST, then, see where my CYA is after the kill?
#3: I also wanted to lower our pH to about 7.2 before starting the kill. I had it to 7.3, but it went back up to 7.5 yesterday! TA is holding steady at 100.
So our plan of attack is to lower the CYA to 20-30 (sump pumping the water onto our VERY dry, VERY cracked yard), then lower the pH back down to 7.2ish, then start the attack.
Current readings: ran out of kit stuff, so using strips
FC: Looks to be over 5 a little, but not close to 10
pH: 7.3ish (strip) .. 7.5ish drops
TA: 100 (drops)
CYA: 30-50 range (strip) .. Leslie's consistently testing at 40.
I can't differentiate the colors on those strips very well.
Any advice would be greatly appreciated. This site is great!