combination NFT and airoponics

[Steve]

Very cool website!
I'm designing a system, combination NFT and aeroponic. I have some questions:
1. I was thinking about making my system out of clear plastic so I could see through it and watch the roots grow and be able to monitor everything inside. I've read that the growing chambers should be dark but I've also been to EPCOT in Disneyworld and saw the tomato plants with the roots hanging out in broad daylight and growing fine. Anyone out there using clear plastic on an NFT or aeroponic system?
2. Are there some plants that prefer to have a growing medium or can all plants be grown successfully with NFT and or aeroponics, i.e. without growing medium?
3. I more or less expect algae growth in my system. Is there a way to control or eliminate it without harming the plants? Is the algae a problem if it does grow in the system?
Thanks in advance for your help on this. It is very much appreciated. I hope I can contribute something in the future.
Steve in NC