12% liquid chlorine is the same thing as bleach only a higher concentration. That would be fine. (But you'll put less of it in the pool.) Keep adding chlorine. Go ahead and add 7 gallons and see what that does for you. It is being used up so quickly that I doubt it will take the chlorine level high enough to be bad for your liner. Keep at it. Retest after 3 hours and add more bleach if it isn't high. Keep doing this -- testing and adding bleach every 3 hours if you can. Hopefully over the weekend, you'll finally get it clear. Are you watching your filter pressure and backwashing as needed? (Backwash whenever the filter pressure increases 8-10 psi over your clean filter pressure.)

It takes a lot of chlorine to convert a baq. pool to a chlorine one. Keep at it! And, run pump 24/7. Also watch your pH.