First, check out the discussion on page 6 of this forum titled Topic: Aldrovanda vesiculosa, how to grow... (Last Post July 10, 2002)
Next, I have grown both the Japan and N. Australia clones and find it easy if you follow the instructions by Doug Darnowski printed in Carnivorius Plant Newsletter. Following is my modification to his approach:
I prepared 3 aquaria with 2 inches of soil in the bottom and a couple of hyacinth plants as Darnowski suggested in his CPN article. In 1 gal bottles, I put 1 cup sugar & a bit of yeast and run the resulting CO2 through tubing to an airstone in each aquarium. I put 2 of each
Aldrovanda types in 2 aquaria in the Humboldt State greenhouse and 1 each in a single aquarium in my unheated greenhouse at home.
The HSU greenhouse has set a min temp of 20C, although the actual temp is often lower at night, and receives only natural sunlight (and daylength). My setup at home also receives natural sunlight, but I supplement sunlight using an 18-in growlux fluorescent with 12-hr photoperiod placed 3-in above the plants; and I also have an aquarium heater that maintains a min temp of 20C. During sunny days, my aquarium has occasionally heated to about 30C.
Now the difference between the growth. The HSU plants became turions in November and have now resumed growth. My plants at home continued growing vigorously throughout the winter with large traps. Each plant has branched numerous times. I expect that the main factors causing this difference in growth between HSU and my home is temperature and daylength, although I also have higher average light intensity because of the fluorescent supplement.
Temperature seems to be very important. I lowered my minimum temperature to 16C three weeks ago. Nothing else changed, although the natural daylength is increasing. All of my N. Australia clone has now produced turions and the Japan clone has reduced growth dramatically. I have now increased the minimum temperature back to 20C and expect the plants will respond by resuming growth.
-Bob-
http://www.humboldt.edu/~rrz7001/