Question
Hey I got the idea that it would be cool to have a venus fly trap in a fish & plant aquarium. I know that fly traps can live underwater for awhile ( I few months if I remember correctly. I have a red dragon fly trap but I wanted to know if any species would be able to live in an aquarium. I know the fish stuff I just need to know if it would be possible to have a venus in an aquarium without it drowning right away.

Answer
Hi Robert,

Sorry to disappoint you with this one.  I don't think it's going to work.  While I'd admit that I don't have any experience growing flytraps completely submerged underwater, from what I know about plant physiology, this one will most likely end in disaster.  

Flytraps simply don't have the same type of adaptive features as aquatic plants to maintain proper osmotic pressure in the cells.  Flytrap bulbs also are not equipped to stay completely submerged under water.  The bulb itself is prone to rotting if it's not properly aerated. (When growing flytraps in pots, the water level needs to be no higher than half way up the pot.  If it's too high and the bulb is submerged below the water level, the bulb rots out and the plant dies.)

Even if the flytrap were to survive for a few months underwater, living among fishes will soon kill the plant.  Flytraps need nutrient poor soil, and the nitrogen waste from the fishes will soon kill off the roots.

Flytraps also need full sun (6 or more hours of direct sunlight) to grow properly.  Most aquarium lights are not strong enough to provide the proper light intensity for flytraps.  The Red Dragon variety is the most sun-loving of the flytraps.  Without full sun, it turns green.

So there are too many physiological factors working against this idea, so I can't offer any specific advice on how to make it work.

Now if you want truly aquatic carnivorous plants, check out the aquatic bladderworts.  There are many native to the United States and they grow very well in outdoor ponds.  The only problem is that many fishes find them very tasty, so while they might survive in a fish tank, they'll end up being very expensive fish food!

For more information about growing flytraps and aquatic bladderworts, read our care sheets online:
http://www.cobraplant.com/caresheets

Good growing!
Jacob Farin