This online calculator begins with some reasonable Pacfic ocean parameters. Free free to input your own parameters and see the results.
Online DownUpwelling Calculator
Heat Exchanger Effectiveness = 0.55 Total Bouyancy = 0.5549 metric tons Total Power = 0.55 megawatts Wave Height = 0.78 meters crest to trough Exchanger Diameter = 0.78 meters 

Down Flow 
Up Flow 
Top Extension Diameter = 0.00 meters Diameter per downflow pipe = 0.00 meters Downflow_bottom_position = 300 meters Number of Downflow Pipes = 000 Downflow Conductance = 000 watts per square meter degree K Downflow Reynolds number = 000 One Pipe Power = 795 Downflow Exit Temperature = 795 degrees C Downflow Velocity = 795 meters per second Bottom Extension Diameter = 795 meters Downflow Egress Density = 795 kg per cubic meter 
Upflow Top Position = 0.30 meters Upflow Bottom Position = 0.20 meters Upflow Conductance = 150 watts per square meter degree K Upflow Reynolds number= 795 Upflow Exit Temperature = 795 degrees C Upflow Velocity = 795 meters per second Upwelling Rate = 795 metric tons per second upWellingBuoyancy = 795 meters of head dow_density = 795 kg per cubic meter 
Note that an upwelling is possible even at a waveheight of zero. This phenomenon was predicted and known as the "perpetual salt fountain". See "Artificial Upwelling of Deep Seawater Using the Perpetual Salt Fountain for Cultivation of Ocean Desert" by Maruyama, S. Tsubaki, K. Taira, K. Sakai, S. in JOURNAL OF OCEANOGRAPHY Vol. 60 pp. 563568 (2004).
Nutrients
In the top several hundred meters in the North Pacific, the concentration of nitrate increases approximately linearly by 6.5 μmoles per liter for every 100 meters depth, and phosphate concentration increases by 0.5 μmoles per liter for every 100 meters depth (Marine Geochemistry edited by Horst D. Schulz and Matthias Zabel, 2006, page 208). With the dimensions given for the device in the pacific, nitrate is added to the photic zone at a rate of 14.95 millimoles per cubic meter of upwelling. The amount of phosphate added is 1.15 millimoles per cubic meter of upwelling. At a rate of 1.4 cubic meters per second, a single upwelling device is delivering 112 kilograms of nitrate and 13.2 kilograms of phosphate to the photic zone each day.