You’re very welcome to the information, sir!
Nope, you don’t quite have the right idea regarding the goldfish bowl kriesel-style nursery tanks. You don’t simply submerge them and then cover the top with netting. They go inside a larger rectangular tank and rest on an egg-crate platform that is just the right height to raise the top of the goldfish bowl above the surface of the water. Holes are drilled through the neck of the goldfish bowl, and these holes are then screened off. Water can thus circulate freely through these screened of holes, but the newborn seahorses are safely contained inside the goldfish bowl kriesel. Liisa Coit has prepared an excellent schematic diagram showing exactly how these in-tank, goldfish bowl kriesel nurseries are constructed and set up. If you contact me off list at [email protected], I will be happy to e-mail you a copy of this schematic, which should make everything perfectly clear.
Best of luck with your seahorses, Nigel! Here’s hoping they are soon churning out brood after brood of healthy young so that you can put your nursery tanks to good use.