BBReefkeeper,
What is your calcium?
CO2 rate and effluent rate should be kept in the same proportion to each other. If you raise one, raise the other, if you decrease one, decrease the other.
If your alkalinity is climing, you are supplying too much to your tank, either turn the reactor off for a couple of days until the DKH falls back into the appropriate range.
When you turn your reactor back on, start out at a lower CO2 rate and lower effluent rate. Check your alkalinity after a few days. When you make adjustments to the reactor, you must adjust both the CO2 and effluent together, both up or both down. Your effluent should be 6.5-7 pH.
Dripping your effluent from above the water in the sump will do little to dissipate the excess CO2. Good water movement and your skimmer should be plenty to gas off any excess CO2.
If your calcium is low, you can use turbo calcium or a similar product to raise it.
I build calcium reactors, and have run many models (including several of my own prototypes), and have never found a pH controller to be necessary. It is a nice luxury, but an occasional check of the effluent pH works just fine for most folks. I always adjust my effluent rate, and then "guesstimate" the CO2 rate. If a bubble of CO2 forms in the top of the reactor, the CO2 rate is too high. If not, I check the pH and make sure it is 6.5-7.
