I spent many a summer snorkeling in the Florida Intracoastal Waterway, which was just a short bike ride from my house. My buddy, Mark, and I would explore the grass flats for hours and catch all sorts of creatures for our fish tanks. We’d even sell fish to a local pet shop, Silent World, for decent pay. Imagine my glee when we captured an octopus—I just knew we were gonna make some serious bank!

I plopped the octopus in our fish tank back home and excitedly called the pet shop.

“We won’t buy it,” said the owner.

“What! Why?” I asked.

“It will eat everything in the tank, then escape in search for more food.”

I watched tentacles snake around the filter and lid of our tank. The octopus was changing colors like a strobe light. I was entranced. I wanted to keep it. “What if the lid on our tank locks?”

“Doesn’t matter. It will figure out how to open it. They are that smart,” replied the owner.

“They can…learn how to open the lid?”

“Yep. Get it out of your tank ASAP.”

My mom drove me back to our snorkel spot and I waded out to the grass flats. With newfound awe, I apologized to the octopus as I scooped it from the bucket. It clung to me for a moment, probing my hands with its suction cups, before disappearing in a cloud of ink.

I never caught another fish to sell after that day. There was more to my marine neighbors than I realized.