The Great Tetraborate Experiment!

[waterbear]

probbaly not since it will take about 97.5 lbs of borax (each box is 4.75 lbs so that is about 20.5 boxes) to raise your 26k gallon pool to 50 ppm borates if you are starting out with no borates in the water. You would also lose a little each time you backwash your DE filter. Using borax to raise pH will add a small amount of borates to the water but you will not get anywhere near the 30-50 ppm range that is required to see it's other benefits.
EDIT: you would also need just over 6 gallons of muriatic acid to neutralize the pH rise from the borax addition and create the boric acid/ borate buffer in the water.