Forgot Rich is the original Grandmaster in Aldrovanda cultivation. Yup, CO2 is very important. I think Arvin posted something in Pitcherplants.proboards.com forum. Link:
http://www.pitcherplants.proboards.c...ay&thread=7553
Marvin, look closely at Rich's pictures, they are in a big area. I grew mine in a 2' by 4' outdoor tank. At first everything hunky dory, Aldro grew well and multiplied. I forgot about the n2o and n3o builtup and eventually algae took over.
Piscesilim also had some Aldro in fish tank. Note that he is an aquascaping expert too. His 4' tank has co2, artificial lighting, some excellent filtration system. His Aldro too went to mulch heaven.