I've never seen a big bottle of Excel in an LFS - only the 125mL size, I think. But if you're going to order a big bottle, get Metricide or Cidex instead. They're the same active ingredient at a higher concentration, and lower price as well. A gallon of Metricide 14 from dealmed.com cost me less than $30, and will probably last me the rest of my life. It's around 70% higher concentration, so you can mix small batches with 10 parts Met, 7 parts water to get Excel-strength. Or check Wet's glutaraldehyde (that's the active ingredient) calculator to be more exact with the mixture.