http://www.plantitearth.com/store/pr...id=414&catid=3

are you talking about this?

looks good. I would get the complete set up. ALL 8. I don't think the controller comes with just one. DId that answer your question?

The ph andthe ppm will be easy to check if you have a controller.. if you don't you may have to lift the plant up out of the container in a single unit. This could present a problem with broken branches (depressing) and even a plant falling over... If you have the extra dough get a compete system..

8 plants is manageable - I bet that system ROCKS!! and it looks easy... you just need light, ph tester, ppm tester and some nutrients... You can even take that system outside!!