It is a heavy glass vase I got from Old Time Pottery I inverted on some concrete blocks so they could swim in from the bottom. You have to get wet to submerge the vase and turn it up under water so the vacuum created keeps the water inside. Make sure you have a heavy glass container or the weight of the water will shatter it. (court. of Rick Brown's fb page - Riverview Flower Farm Growing Florida Friendly Plants)
Award-winning images of some of the world's smallest life forms
This little critter is known as a water bear or a Tardigrade. In 2008 they were the first animal demonstrated to be able to survive the vacuum of space. They are virtually indestructible survive being blasted w radiation, intense pressures & years of desiccation. Specimens were launched into space by Swedish scientists & they returned unharmed after 8 days.