Science Buddies: "Ask an Expert"

I'm in the middle of my five stage water filtration system and need to interview someone whom knows about the subject. My intention is to filtrate grey water and filter it in to safe drinking water. The fist stage of my water filtration are to make the grey water pass through a series of thick sponges. From there the water will go to stage two, passing through the water lilies, which are known to clean water from bacteria. Then water will pass to the third stage which is the classic, gravel, sand and active charcoal filter. From here it will pass to the crushed mornings seed which is known to attach to particles dirty water and takes them to the bottom. Stage five will consist of making watter pass through cilantro leaves which will balance the Ph for the water.
I have a series of questions for people who know more about the subject.
With my filtration system, can I successfully filter more than grey water?
Which system of more efficient the crushed moringa seeds, or the crushed cilantro leaves?
What can I do to make greywater last longer for filtration?
Per my project using the five stages, is there a more efficient way to naturally filter great water than what I'm proposing?
What would you r comment I do differently to make my project more efficient?

Your input is greatly appreciated

There may not be an Expert available to help with an interview assignment. But I encourage you to review the guidelines for interview requests. Research-type questions (questions you should be answering with your project or research, for example) will not be answered. Please review this information here:

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