I hope I'm not too late in the game for this thread, but just a tip from someone with plateing knowledge, not sure it's been covered here as I haven't the time right now to read all the previous posts, but what is your plate structure? You should avoid flat plates at just about any cost as to get the most reaction you'll want increased surface area of your anodes. You can probably get 100-200% or more output out of an existing generator if you increase the surface area of the plates by corrugating them or using plate grids instead of flat plates elements. The same goes for the cathode.