Ah, 5 days, not too long. There are still MANY variables that we don't know (location [sunny, rainy, cloudy], cover?, recent chem. balance problems, etc...). Can a neighbor put a gallon or so every other day until you return? I wouldn't recommend pucks as your CYA is at the border according to recomends here. Even if your chlorine goes to nil for a day or two, it shouldn't hurt it (if no problems currently and water is clear).