Perhaps duckweed? The Savage Garden seems to think highly of it. You could try planting some bog plants in containers and put them in there. My landscaping book says, for a bright spot, arrowhead arum, blue and yellow flag, cardinal flower, cattails, dwarf umbrella palm, imperial taro, lotus, pickerelweed, water canna, water lily, water hawthorn, and water plantain. For oxygenators, you can use anacharis, cabomba, hair grass, hygrophilla, parrot's feather, sagittaria, and vallisneria. Since you can't use water hyacinth for a water cleaner, you might try to find some freshwater mussels to put in. The aldrovanda might even be able to trap the larvae if they have a free-floating stage. I dunno about water poppy, but it's probably worth a try if you have space. What kind of planting are you thinking about?
~Joe
PS - It's kinda vauge as to what types of plants those are, so I'm not certain they're entirely submersible. Shouldn't be hard to find out though.