Not really sure of the application you are talking about. I do put plants in my filter system for all my aquatic turtles. If you're talking of a similar filter system just used for a tortoise water feature in that enclosure, then it would be the same thing. Many if not most of the plants you can think of will grow using the filter system as a hydroponic type system. And they do great! I wash off the roots of the plant and stick it in the filter! The plant takes off!
One of the easiest to grow plants indoors is pothos ivy. It is one of the most common houseplants you see for sale. Normally grown in a pot like any other plant. It makes a great tortoise or turtle enclosure plant. Probably the best growing low light plant you can use. With roots in the water, it will grow and trail everywhere. My tortoises do eat it so that limits the growth to what they can reach. These plants can grow over 20 feet! They are one of the best at filtering water removing a lot of nitrate in the process.
You will see some places list this a toxic to animals. It has an irritant (raphides) in it that effects dogs and cats, and should be kept from them. However, it has no effect on tortoises and turtles and can be eaten. Some tortoises will nibble on it, others leave it alone. It creates a nice visual barrier and hides for the tortoise as well.
And yes in my circulating waterfall / water feature. I am hoping to find something :
1) tortoise safe
2) that can help filter water
I was thinking about having something alive floating in her water bowl. It is still the central reservoir for my water feature.
I was also contemplating setting some cork rounds down into the filtration sediment (eco earth) and putting some plants in those.
Any thoughts?