Santa Barbara Aquaponics 2021

Feds Slash Colorado River Release to Historic Lows.

Be sure to play with the slider on the top image to see the difference between a full reservoir and where we are today. If you’ve seen your local reservoir, it might look similar to Lake Mead.

So why does aquaponics matter? Because the Colorado River, like nearly all of the rivers in the western U.S., are oversubscribed and there no longer is enough to go around unless you have a series of wet years. Don’t believe me? When was the last time the Mighty Colorado actually reached the ocean? 1998.

For regions of the world that are or are likely to be under water stress, having alternative methods of agriculture that use much less water than traditional farming is worth learning about. With as young as aquaponics is in the modern sense, I’m excited about the next 20 years and where the movement will be!

We are trying to expand our fish area by putting channel catfish in our deep water culture troughs where we grow vegetables. Since these catfish are only 3-4″, it seems to be working out ok so far since they aren’t trashing the roots of the plants and don’t seem to be eating the mosquito fish….yet. We did notice that when we pick up a raft, we have to be sure we don’t get catfish stuck and pulled out of water! This brings up the question, if we can keep catfish in the trough, do we really need a fish tank?!?

The short and admittedly not edge-of-your-seat video is short and was taken when our bell siphon is draining water into the trough, hence, strong flow left to right.

Tomato plants are thriving in our 18″ deep media container. They love the nutrient rich water flowing from the fish tank on the left and the fact that the entire container floods and drains every 8 minutes, exposing the roots an alternating bath of nutrient rich water and oxygen rich air.

The tomatoes however, have sent roots into the bell siphon, restricting the flow in the siphon outlet, which keeps the siphon from starting reliably.  Our water levels were getting higher than normal before the siphon starts, an indication of something wrong.  ROOTS!!! Here you see we had to dig out the media surrounding the bell siphon.

Randy lifting off the outer shell of the bell siphon. Those 5′ long roots were growing into the high flow of the 2″ outlet.

More of the hydroton media removed. Interesting how the roots of the tomatoes do such a great job holding onto the media that would otherwise be rolling down to the lowest point. The roots held it up like a wall!  See the two parts of the bell siphon, the vertical 2″ PVC that drains downward to the lower elevation trough. The larger 4″ pipe on the left normally is placed directly over the 2″ pipe and is the outer shell where water flows into the bell siphon from the bottom and up towards the top opening in the 2″ pipe.

Our solution was inserting a 7 gallon bucket as an outer chamber for the bell siphon to keep the roots and media away from the siphon. By cutting large holes in the bucket walls and covering it with 1/2″ plastic mesh, the bucket was now a ‘pre-filter’ to keep the media from getting into the bucket.  Once the bucket was secure, we refilled the tote with media but not so high that we don’t bury the lid of the bucket.

When we unscrew the bucket lid, we now have a ‘window’ into the bell siphon. While we will normally have the lid screwed on, we can unscrew it to cut out any roots to keep the siphon clear, and also to show people how a siphon works.  It is now easier to maintain and observe, and we can have tomato or other plants in our media area. We just need to cut the roots occasionally that grow into the new outer chamber. All in all, while it uses more materials, it results in a better, more reliable bell siphon, which counts for something….