Photonoid@aol.com
I figure I would put my 2 cents in on this topic sense I have a little knowledge about it. I do not keep plants in with my DBT because they would trash them but I do keep a lot of Fish and have some tanks set up just as live plant tanks. I agree with everyone that an air stone will provide water movement which in return will help you with the protein film. The film is cause by still water and the nutrients given off by decaying plant matter. I keep a few very rare live plants that do not like moving water and have to live with the film on the surface of the water. I suggest you get a low power filter such as a Fulval #1 very small cheap filter and place it just beneath the water level. They are just strong enough to move the water around a bit to prevent film build up. I also suggest removing dead or broken leaves before the start to decay. This works great for me and does a perfect job. Most plants that can be found at your local pet store are good such as the sword and arrow plants as well as many others, just stay away from lace plant they are very fragile and require certain conditions and banana plants, the funny looking little plant that looks like a bunch of bananas, they release toxins into the water as the rot and can kill any fish you might have. Lastly some small fish are good to have in with plants, and cheap fish usually work well just stay away from gold fish, they love to eat plants. Well that is all I have to say Dave