I haven’t had much luck growing plants on the Shrimphaus river. Mostly they dry out either immediately or eventually, or sometimes they rot away. This roots and bottom bits wet all the time but leaves out in the air niche is pretty challenging. Some internet digging revealed plants that thrive in this setting are called marginal plants: those growing on the margins of bodies of water, and they are popular for people with ponds. Ok, so that’s the right setting, but outdoor ponds are much larger than the Shrimphaus so only the smallest marginal plants might work. Some shopping around led me to try Bog Arum (Calla palustris), Golden Buttons (Cotula coronopifolia) and Golden Creeping Jenny (Lysimachia nummularia ‘Aurea’). All of these are listed as growing to a maximum height of about 6 inches.
The plants arrived well-packed in wet newspaper and the first surprise was how big they all were. The pond world operates on a much larger scale than the aquarium world!