I've been using the TFP method the last two seasons and it was excellent. Unfortunately, this summer has been ****.
I take readings all the time, using a Taylor 2006.
Current reading FC11, CC0, pH 7.6, TA 80, CH 175, T 76, Stab 100, Borate 50
It started with small patches of light green on the bottom of the pool in July. The stabiliser was 60 then.
I shocked the pool and went on vacation, whereapon my pool turned Green after 3 days. Somehow stabiliser measured 0 by someone and someone added another bucket of stabiliser to raise it to 80-90.
When I got back, due to high stabiliser, I had to raise my FC levels to crazy levels for 2-3 days (40-50) before I cleared out the green and had no loss of FC overnight, no CC, and clear water. Filter cleared out the grey stuff and backwashed.
I then let my FC drift down to 6, but after a week, I've had the small patches of light green return. I've increased the FC to 11-12 but it doesn't seem to be helping. It's been like this a month or so.
My wife is going crazy brushing the pool and vacuuming every other day or so. I tried a clarifier product with not much effect. I added borates which resulted in really nice clear water, but hasn't stoped the light green patches. I also removed the ladder (found some green on the inside of the rubber bumper and bleached the heck out of it) and scrubbed the skimmer like crazy after noting some green there, scrubbed the light, steps etc like crazy for weeks as well.
My neighbour swears by weekly algaecide and I'm starting to think I should give it a shot. I have Poly oxyethylene dimethylmi... dichloride 40% that I soak my pool cover in over the summer. Is it time to add this to the mix weekly? What would be the down side? We only have a few more weeks before I close the pool for the season.
Starting to lose the faith, Tim