Am in a different part of the country but you wont find decent silicone in a hardware store. That stuff is all junk compared to aquarium adhesive. Don't use GE on anything above a 20 gallon. I use scs 1200 which some pet fish stores keep in stock around here. The guy at the biggest LFS here in winnpeg makes 600 gallon tanks out of it. I have made an 80 gallon and tested the top brands side by side myself. The dow you mentioned is just about as good but takes too long to cure and can be hard to find.