My guess is that your pH is so low that it is causing the bleeding, but that's simply a guess. If your test strips max at 6.8, and you haven't been able to move it at all with 5 lbs of Borax, then it's probably a whole lot lower than 6.8. I gather you're using trichlor pucks or dichlor powder for chlorination? If so, it's time to stop using those, since they both raise your CYA, which is pretty high, and drive your pH down. However, you really, really, really need to get a drop-based test kit. You can pick up one of the cheapie OTO chlorine and pH kits for less than $8 in most places (uses red and yellow drops for pH and chlorine), and they will be WAY more accurate than the test strips you're using, which are mostly unreliable.
Also, you need to up your chlorine a bit--with a CYA of 150, you really need to keep your chlorine at 8 ppm or higher.....
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