I love plants in general.. and aquatic plants are my new obsession, lol. I'm creating a couple of small bog-plant dishes and also experimenting with Walstad/NPT style tanks soon..
I've seen so much photographic/ anecdotal evidence of these tanks not only causing plants to flourish madly in a relatively short period of time but also sustaining a healthy balance in the tank for years, with many fewer water changes that a regular sand-substrate tank. I have all the things I need to get my empty 8-gallon going, but I'm not sure whether I'm moving house or not, so.. it has to wait!
Twilight, I LOVE your floating planter! Organic potting mix or clean topsoil with no added ferts or water saving stuff.. sand on top to keep it from floating up.. is the advice I've had for planted tanks, so I'd suppose the same goes for water features. I'm using organic mix, as I live in the city and don't trust my topsoil to be free of nasty stuffs. You might be interested in some of the clay bead things riparium people use in their floating cups.. they're very clean, okay with fish in the tanks, and the plants seem to do well in them.
I'm also trying a recipe invented by a poster on another forum for a soil base that creates a natural carbon release, using Blood & Bone and a little crushed marble under the main substrate. Reports from other members who've tried it are great - and gosh, incredible plant growth, plus the stuff apparently lasts for around ten years before breaking down - the only problem being when too much B&B is used and the tank gets stinky.
I haven't tried any bulbs yet but it was good to read about the bulb dropping off and it all being fine.. these hints and tips are so valuable!