pH optimization of chemicals

[sgbaird]

I.e., autonomous titration like many other existing demos.

From #77:

Purchase a pH sensor and replace the red/green/blue food coloring dyes with other chemicals (I forget which ones specifically, but there are a few manuscripts that do pH optimization). Still probably in the < $200 and < 2 hrs setup, since the only additional materials are the pH sensor, cabling for the pH sensor, and the chemicals.

Flow-through would be ideal, though this might need to be a hacked together flow-through similar to the hacked together flow-through cuvette.

Least amount of work would probably be to adapt the relevant bits from Adafruit's reefpi tutorial and use something from Atlas Scientific or similar.

• Atlas Scientific pH Kit
• Phidget pH Kit