Ahah! I don't know diddly about aquatic plants yet, but this I know about.
Lucky bamboo is in the Dracaena family and is not in fact a bamboo, nor is it an aquatic plant. As it is sold, it isn't a growing plant but a stem that was (usually) trained to grow in a spiral and then lopped off and stuck in a vase of water. As is the case with many herbacious plants, it roots when placed in water.
The amusing part is that Dracaena is a common houseplant (grown in soil) that wasn't especially popular until someone decided to sell it stem-only as a "lucky" bamboo. It is a convenient "houseplant" for people though, given that the stems will stay in this rooted stage for a very long period of time without dying.
But there isn't anything wrong with them, and you can put them in your aquarium if you like. They will probably flourish there more than they would in a regular vase, given the nutrients in the water. If you ever get tired of them you can put them in a pot of soil and grow them as a houseplant.
One word of caution is that some imports of lucky bamboo from Asia harbor the tiger mosquito which often carries diseases. Rinse them well when you purchase them.
