big gardens seem to not have the ebb and flow

[Steve]

how come all the big gardens seem to not have the ebb and flow but have the drip. it seems that way in the pictures i checked out. is there a reason for this? steve

[Ron]

Because the size of the reservoir and pump needed for a large commercial gardens. The more volume of water needed to fill a system the lager a pump needed to do the job.
I use 50 gallon drums for 100 tomato plants and they use every bit of it every 24 hours. That means mixing fertilizer everyday for each 100 plants. I will be buying a 200 gallon tank soon for my spring planting.