Use plain bleach. I actually use a combination of pucks, cal-hypo, and bleach but keep an eye on CYA and Calcium Hardness and use the CH and pucks as appropriate. CH isn't an issue with a vinyl pool but I use the cal-hypo for convenience and just make sure the hardness doesn't get high. My pool got away from me this year as we had a few warm days and I was out of town. One of my friends used the words disgusting swamp and cesspool. I do brush with the vacuum brush but also can hook the hose to a return line and put it in blow mode. That kicks up algae and dead stuff in places you can't easily or safely brush. The filter then does the rest. Took 5 days to get it clear again.
Al