Frozen jugs vs ice packs for coolers: Frozen jugs win for longer-lasting, cheaper cooling

Frozen jugs last longer than ice packs because they have less surface area per volume, so they melt slower. They cost nothing (tap water in empty containers), won’t leak slime if cracked, and give you cold drinking water when melted. Ice packs are fine for small lunch bags, but for real coolers, frozen jugs are the better, cheaper choice.