I would use the one you have first. Learn how it works.Then I would get the second unit.That way you know how it works and what you want to do to improve it.The ebb is one the best, I use 5 1/2" net pots. clones in rock wool cubes in the net pots filled with hydroten.5 1/2" pots in the tray filled with hydroten.This way when its time to flower I pull the net pots out carefully and put them in the flowering tray and fill with hydrotens.This works for me.But you will find what works for you.Well that's my two cents.PEACE