Btw if you want fast growth of the wisteria, in my experience you can cut them about 3/4 the way up the stem and plant the part you cut. This will send out lateral runners from the original stalk that cover a lot of area in a month. With that stuff you can even plant a leaf that has been broken off and it will grow. The salvinia minuta on top should just grow like crazy anyway. The ludwigia you can do the same as the wisteria one it reaches a large size but sometimes it sends out buds anyway. When I got my java moss in December, it was about half the size it is now so you could expect the same growth rate.
Anyway, where did you get your fish? I would love to get some of my own.