Being Friday I thought it would be fun to get a list of item (gadgets, gimmicks, exciting 'new tech', etc.) that you purchased over the years that you can honestly look back on and say "yep, wasted my money on that". It's OK we are only human and we won't judge you (much). Off the top of my head when running freshwater I fell for the undergravel filter "you'll never have to clean your substrate if you use this" deal. If you want a giant detritus trap yeah those work GREAT!