Can I visit and collect data on your aquaponic garden in the Northwest?

[Joel Bidnick]

Hello, fellow aquaponic practitioners!

I’m Joel, a grad student of horticulture at UW, and I’d like the opportunity to visit your system if you use flood-and-drain (or ebb and flow) grow beds within a day’s drive of Seattle. I recently built a conceptual model of O2 concentration in the root zone of these systems and I would like data for calibration. So I would visit you in April, check out your system, and use a O2 concentration probe in your grow bed.

Generally soil air has a much higher CO2 concentration and a lower O2 concentration due to soil and root respiration. We know the root zone in AP systems act as a robust biofilter and must respire at a high rate. Flood-and-drain aquaponic systems are unique in that bell or loop siphons - or even a system on a timer - drain extremely quickly relative to edaphic media. When water leaves the grow bed, ambient air is pulled into the media, replacing the water and resetting the CO2 and O2 concentrations back to ambient. Since I have seen varying recommendations on how often a system should be totally flooded and drained, I hope to answer a couple questions with this model: Does the drain frequency really matter? And does O2 become limiting for plant growth with very low drain frequency? With this data, I hope to better inform best practices for flood-and-drain aquaponic systems. 

Of course, I will share the results with this forum. The more systems I can test, the better the model will be. Please send me an email to let me know right away if I can come check out your system. I think it would be fun to see other's projects. Happy Farming!

- Joel

[e-mail]

[Mary Hunt]

Hello Joel - I'm in Port Townsend (45 minutes from the Bainbridge ferry).  I'm running a 5 inch gravel/flood and drain system for 100 sq. ft. bed. You are welcome to stop by and test the waters in April. I can be reached via this thread or call/text me at 714-926-1223 to set up a time.    

I am also interested in the nutrition levels of aquaponically grown food vs. organic or hydroponics. Do you know anyone at UW doing that work? 

Mary

[Michelle Tonkinson]

I'm in Vancouver, WA.  I have a 650 gal. fish tank and 2 media beds going that use flood and drain (Bell siphons).  I grew tons of kale and lettuce all winter!  Not much happening at the moment as I am letting my kale go to seed to collect, but you are welcome to come measure whatever you like.  I also have a hydroponic tower going.

Michelle

[Joel Bidnick]

This is great, Michelle. I should be getting access to my equipment soon. If I get it by next weekend, are you going to be around (23rd and 24th) ?

Michelle Tonkinson said:

I'm in Vancouver, WA.  I have a 650 gal. fish tank and 2 media beds going that use flood and drain (Bell siphons).  I grew tons of kale and lettuce all winter!  Not much happening at the moment as I am letting my kale go to seed to collect, but you are welcome to come measure whatever you like.  I also have a hydroponic tower going.

Michelle