Yes and no. For large scale hydroponics, done outdoors or in greenhouses, concrete is ok. But for smaller scale hydroponics set ups, like at home, or something that uses continuous flow or ebb and flow watering, creating a functional, watertight, easily washable, moveable hydroponics set up is really hard without plastic. If there is a good solution I am all for it. This is actually one of the things that is preventing me from setting up a system is I am trying to limit plastic use.