Comment

Comment by David Hart on September 13, 2011 at 6:18am

Good idea with the stand pipe with the holes in the bottom.

Comment by Rob Nash on September 13, 2011 at 6:13am

per the original design (Tom Speraneo @ S&S Aquafarm) the beds had no standpipe or siphon, they were just a "restricted flow" drains with timers. i have modified it to include a 1-1/2" standpipe with holes at the bottom, still using timers. this acts as the restricted flow, but with a safe guard- if the holes get clogged the water overflows the standpipe, not the bed.  i will try to document this and post later.

Comment by David Hart on September 13, 2011 at 6:06am

Hi Rob, what size stand pipe and drain did you use in your gravel beds ?

Comment by Rob Nash on September 13, 2011 at 5:52am

I like gravel beds for sure. Lettuce is well suited for the rafts, but everything i put in the gravel does better. the giant head of Black Simpson my daughter is holding was grown in the gravel. to answer your question, i will continue to use the rafts for the lettuce and kale. With the 300 - 600 heads of lettuce per week, its nice to work off the boards. the rafts cant be beat when it comes to ease of use. An experienced farmer friend always tells me... its all about Your Time.    

...this is a hybrid system, where we run from the gravel beds through the rafts back to the tanks, without separators and filters. works great, with minimum cleaning and no waste!

Comment by Two Jay on September 12, 2011 at 9:27pm

I see a lot of gravel beds, and a few DWC ones as well.. What is your preference for lettuces, how about in general? The pictures and your system look great!