My ph is low and it laughs at Borax

[waterbear]

Aylad is right on the money. Listen to her! (particularly about NOT using any trichlor!)

[CarlD]

Ditto!

Further, your CYA DID come down: trying to read it at night by flashlight gave you a false score much lower than it was. The light must have made the sample look less opaque than it was.

The CYA test is PARTICULARLY sensitive to you always doing it the same way.