Steve,
Glad to hear your project is coming along.
I'll add this post on calibration of my system so you have an idea where to start.
Calibration of Peristaltic Pump:
First secure an accurate graduated cylinder > 200 ml and a stopwatch or other timing device so you can measure how much is being pumped over a period of time.
Start by dividing the speed control of the pump into equal divisions unless it has this done (mine did not). I then started the pump and counted the revolutions per minute and divided this by the number of lobes on the pump to determine how much is pumped per revolution or lobe cycle. Set the pump on each setting and time for 1 or 2 minutes recording how much is pumped.
Use these reading to figure the amount pumped in an hour. I created a spreadsheet to make my life easier. I then verified the calculations over an 8 hour period.
Using the bleach calculator I was able to figure out the PPM increase to expect for a given period of time (assuming no consumption from algae etc.). I did this at night to try to cancel the effects of solar burn off. I found I could predict the outcome accurately using this method.
The next thing I tried to do was calculate the PPM loss due to solar burn. This turned out to be a somewhat fruitless effort because of all the factors (clouds, date, water temp, pump run time, swimmer load, etc.) Needless to say I test very frequently (FAS-DPD method) and adjust the pump to keep the range within Ben's Best Guess Chart for my CYA level (around 22 ppm). After a period of time I was able to come up with some averages to work with.
I have since started increasing the CYA toward 30 ppm, to try to determine the best overall ratio. My daily CL burn off was about 2-4 ppm. if the pool is uncovered all day.
My experiment will continue for a year or two but things are favorable to this point. I may start looking at controllers if the price comes down but so far the cost/benefit ratio is still out of whack in my opinion. Any further questions --- please ask.
Bookmarks