i assume you're talking about water bags to hold your winter cover in place once your pool is closed. we save 10-12 of our bleach bottles after they are empty, and store them in our shed. come closing time, we fill the bottles up 1/2 way with water, and put them on top of our cover. cover stay down, no broken water bags, and no ballooning of the cover in the wind.....and they're free!