This is easy with a system like that one grow rocks are fine.

Make sure your overfill tube is working because you will need it. Ebb & flow in something like this should work for plants up to 24-30" tall plants at finish. That's not much of a yield but if you do enough then it adds up quick. You will find if the plants root system gets too large they will clog the 1" hole you are using as a drain.

That is why I said to make sure your overfill tube is working.

Happy growing

In this Saturdays pod-cast I cover Hydroponics nutrients so you may want to check it out.
Zandor Reviewed by Zandor on . ebb and flow I want to set up my first hydro system, but befor i do I want to have everything on paper, ( blueprint) before I start the set-up. The system below is what i'm planning. it's a 11 plant system using 2 liter bottles. I have a few ?'s. 1- What is the best medium for this system? 2-I'm thinking about using clay pebbles, are the clay pebbles fine or should I mix in perlite? 3- If I only use the clay pebbles, how many times a day should I flood the system and for how long? 4- If I would Rating: 5