I guess it's not that big of a deal but I have never accomplished it before. My U. gibba that I have in an outside bog has sent up a single flower stalk. I think the set up (now about 2 maybe 3 years old) has found a good balance. All I do is add water, I don't do any cleaning or anything. There is some algae along the top of the water with floating plant pieces (and U. gibba) but once you get past that the water is crystal clear to the bottom. I even have damselflys running their whole life cycle in here, (which I read are very sensitive to water conditions) there are tons of their molting skins around on the grass blades and lilly pads, even on the side of the plastic container. They are cool to watch in the water as they swim side to side lol
In the first picture you can see the mat of U. gibba, algae and other junk and if you look on the smaller of the two lilly pad leaves you will see the damselfly larva sitting there. Max I've found in there at any given time was 11. I really think this tank is ready to give aldrovandra a try. Please PM me if you have any The last picture is just a wide shot, you can see the flower near the bottom left.
Sorry for the not great phone pictures.
PS- this reminds me of this topic: does gibba need peat? I think it further points towards peat being in the water is helpful.