Coles has the Rehydraid Electrolyte Effervescent Tablets in Grape (10 pack) for $7.00 today, which puts it right in line with where Woolies is sitting on special at $6.95, a saving of $1.75 off the regular $8.70. These dissolve straight into a water bottle and they're a handy thing to throw in your bag for hot afternoons, after sport, or any weekend where the sun's going harder than expected. If you're already doing a Coles run, it's worth grabbing a tube rather than paying the $8.45 IGA is asking even on their marked-down price.