[Bontempos]

Hello,

I'm trying to make an experiment with ph indicator based on the famous traffic light reaction experiment. My project intends to switch colors by attaching a mechanism able to shake the solution.

I am using the same materials and proportions but I need some adaptation for my project.

The current recipe I have allows me to go back and forth the colors around 6 to 8 times before its cycle becomes less noticeable.
Or, if in order to display the color green, the mechanism must be turned on and this consumes all the dye very fast so number of cycles is also compromised.

I wonder if is there any other recipe to react with a ph indicator in the same fashion which could last for more cycles or even for days.

Now, I am mechanically shaking the solution. But I also wonder if I can change the ph of the solution by adding some voltage to it and thus affect the indicator color. Any suggestion or references would be of great help. Thank you all