What's worst case scenario?

This is my first year with a pool. I've used only the BBB method. I must admit to neglecting my pool chemicals for the past 3-4 weeks. After removing the solar cover to vacuum and prepare for closing, I noticed green stuff starting to grow on the shady-side pool wall. It wasn't horrible and was easily brushed off. I vacuumed, brushed, and then shocked with chlorine. I tested the water with my cheapo Walmart test kit but really, for me, its a best guess as to what the numbers are. The water turned an orange color. Then I tried to use the shot glass method for testing but am pretty sure I messed that up (used water from my dehumidifier to dilute the pool water).

Anyway . . . . long story long, I can't find Polyquat 60% at our local pool stores (3 of them). One store told me over the phone they had a "three month" algecide which would be 60%. I drove there to buy it and it wasn't what I asked for, it contained copper which I know is a no-no.

So, I am opting to not add the algecide. If my pool is clean, and I believe it is, things should be fine come spring.

However, what if my pool is not as clean as I think it is. What is the worst case scenario?

Central Illinois
Air Temp last weekend 85 degrees
Air Temp today 41 and dropping!!
Water Temp last weekend 70 degrees
Used Doughboy
28' round
new sand filter and pump (don't know what kind)

Worst case scenario is that you'll have green water on opening and no CYA, both of which can be fairly easily taken care of. Keep your chemistry up until the water temp is 60 ish or below, then shock it one more time and close. Don't worry about it, it'll be farly easy to clean up.

Welcome to the forum ! :) I'd say the worst case scenario is a tree comming down on your pool :D Seriously, the worst case is that you'll get an algae bloom and have to do a lot of cleaning and add a few cases of bleach (or more). I believe that most people here use the algicide as insurance against algae - if yoou have sufficient available chlorine in the water, the algae won't grow. If you're not going to use the algicide, add an extra bottle of bleach when you shock the pool prior to closing, just to be sure that you've killed all you can before slapping the cover on. (I assume you follow Ben's Best Guess chart for shocking)
IMO, you may have a little algae in the pool when you open in the spring, but it shouldn't be too bad - just in case, plan to open the pool a week early next spring to allow for any cleanup that may be required.

I'm in Northeast PA and have never used an algecide. I keep the equipment going as long as possible, usually mid November before I blow the buried pipes, so I can circulate a little every few days and keep the chemistry right. I also open early and the only time I get an algae problem in the Spring is when I get lazy and cheap so I don't circulate as much and the water warms a little. I'll see it and get right on it.
Al