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Wondering what growing media to use? You’re in luck – an Ebb & Flow system can easily accommodate a variety of growing media. The system is great for using anything from Rockwool to hydroton. The only thing you will change is how often you flood the tray each day and for how long.
One of my favorite growing media to use in an Ebb & Flow system is hydroton. Hydroton is expanded clay pellets that work as an anchor for the plants roots. It stabilizes the plant and gives the roots a media they can grow easily through. Hydroton does not have much water holding capacity so for this media, you should be flooding the table every two hours for 15 minutes. Keep in mind each setup is different so flood times and number of floods will vary. If you were to go with a growing media like Rockwool you would be looking to flood less often. It all depends on how much water the growing media can hold.