[Delphinus]

Hi ... just my $0.02 ... "techni-ice" and/or gel packs may last longer and that's great, but what is that stuff? If a pop bottle with frozen water leaks some "coolant" into my tank, it's only fresh water so no catastrophe (presumably). Just be very careful when using the other stuff. I think if it were my tank, I'd just stick with frozen water. Too many things can/eventually do go wrong, why chance leaking some petrochemical (or whatever it is) into the tank?