Growing up in the 70s, just about every comic book I read had the above ad. I was reading everything from Conan The Barbarian to The Incredible Hulk. Those sea monkeys were pink and had human faces, they were pink and had tails like monkeys. There was a father, mother and kids. I really wanted to order from the USA and in those pre-Internet days, there was no way I could see if they really resembled the creatures in the ads. My imagination went wild, it was like having a species of mermaids as pets.
In fact, sea monkeys are merely brine shrimp but sea monkeys sounds so much better especially to a kid who didn’t have the faintest idea what brine shrimps were even if someone had enlightened me. The only thing that stopped me from ordering was I had no idea how to get the money over to the supplier in the USA. Not like there was PayPal then. Just as well I never ordered otherwise I am sure I would have been sorely disappointed that they looked nothing like those in the ad.
Brine shrimp are translucent and while they probably look quite nice swimming about in an aquarium, I think that keeping fish as pets would have been more fascinating. I just wonder how many curious kids would have ordered in those days.