We've been using the BBB method since starting up our pool on July 1st. It's 3740 gallons and to date, we've used roughly 95oz (almost 6lbs) of borax to adjust the pH. The fill water was from the town supply and it's pH was very low. Our TA is currently around 90-100 and the pH has been holding steady around 7.2. We'd like to be around 7.5, but are concerned about adding any more borax to the water. We've read that unlike chlorine, the borax will remain in the water and becomes toxic at higher concentrations. Our question is, how much is too much? Have we already used too much for a pool this size?
As for the rest of the levels, our CYA is 30-40 and we've been holding FC around 5-7. Also using 4-6oz weekly of Stain prevention and remover to keep the water clear. The BBB method combined with the apparent metal(s) in the town water likes to turn the pool a transparent green color.