The excitement this month in our world of aquaponics was plumbing. Farmer John installed the plumbing hardware for one garden bed, fish tank & sump tank. He’s still working on getting the ph & bacteria levels correct before adding fish.
Three grow beds in a row. Sump tank underneath the middle grow bed. And, the main fish tank on the right.
Farmer John used some black poly pipe that we had lying around to figure out how he wanted the plumbing set up. The poly pipe is flexible, making it easy to work with.
May 2014 update: After figuring everything out, Farmer John switch the poly pipe to pvc pipe.
Our grow beds work with an ebb & flow system, meaning the water level is not constant. Water fills the grow bed, then drains out in a continuous cycle. To drain the water, Farmer John made a bell siphon for each grow bed. There are three main parts that keep it running smoothly – the standpipe, the bell siphon & a gravel guard.
Standpipe: This is the drain. When the water reaches the top of the standpipe it drains down into our sump tank.
Bell Siphon: An air tight cap over pvc pipe with a notch at the bottom creates our bell siphon. Water flows in through the notch and creates a change in pressure. The water then drains down the standpipe until the notch at the bottom lets air in. This creates the constant ebb & flow in the grow beds.
Gravel Guard: PVC pipe with slots cut in it from a table saw. This is used to protect the bell siphon from the growing medium and prevent the notch at the bottom from getting blocked.
EXPANDED CLAY PEBBLES
We chose to use expanded clay as our grow bed medium mainly because they do not affect the pH in our aquaponics system. But also, the pebbles are porous so they hold moisture well & gives a place for the good bacteria to live. The round shape makes them easy on our hands when working with plants.
An aquaponics system needs good bacteria. To speed up our system getting the good bacteria, we placed the aquarium filter from our aquarium that housed the goldfish & minnows into a grow bed.
Starting lettuce & Chinese cabbage seeds right in the grow bed. The seeds are so tiny, Farmer John placed them on a paper towel to keep them from draining away.
June 2015 update: The paper towels probably weren’t necessary. They didn’t hurt anything, but we’ve never used them again & our seeds start just fine.