Yesterday there was a new guy at my favorite fish store. He was recommending tinfoil barbs to a woman with children.
She said, "And they'll be ok with the goldfish?"
He replied, "yeah cuz they're pretty peaceful and fast enough to avoid him."
Her, "Even in a twenty gallon??"
He says yes, sounding completely lost.
She makes a I-don't-believe-you face while I turn and shake my head behind his back.
Then she says, "what about these?" (Cichlids)
He said they get too big.
She said I thought fish were limited by the size of the tank.
He looks extremely unhappy and says "to a degree yes, but..."
So I said, "their spine stops but their internal organs do not. So you shorten the lifespan of your fish," in an empathetic tone.
He said, "yeah so I don't really recommend that."
I gave her the forum a while later and talked to her about her fish...
He did check to make sure she dechlorinated her pwc water.