This is a good one, I have told it to all our other employees and they laughed their @$$es off.
So this guy comes in, and he's a decent guy, done freshwater for years, knows his stuff. He has a 70ish gallon tank, regular T8 light and a fluval 405 filter, and it's empty now. He wants to convert it to saltwater but doesn't know the first thing about it and needs me to explain it to him. Great, that's fine, I set people up with saltwater all day, easy. What he said next was hillarious though. He said he went to Petland and asked them but they just confused the heck out of him. This young girl tells him his fluval filter is useless for saltwater (meanwhile I have the same one on my 55 reef), then they proceed to tell him that in order to use it, he will have to install a light INSIDE his filter and grow CORALS in it

In a fluval 405!
She must have been thinking of a refugium...
So I explained saltwater to him, sold him some live sand, live rock, and some salt, and he was happy he didn't need to light his canister filter. So I say thanks to Petland for that sale and our new happy saltwater customer who will continue to shop at our store and avoid Petland!