Using sensor input to light WS2801 LED pixel strips

Other Hardware LEDs and Multiplexing
1

I'm trying to rebuild an arcade game, the style where you direct water flow through a flow rate meter, in order to move a horse to a finish line, or inflate a balloon until it pops...

In this case, the game looks like the side of a building, with WS2801 LED pixel strips (an older version of them) laying out flames in red on the building side.

The idea is that as you direct the water through the flow meter, the LEDs will change from red to blue, moving from bottom to top.

I understand addressing the LEDs to change the color, I think, but I have no clue where to start when in comes to tying the color shift to the input from the flow rate meter, and using it to shift the color of the LED pixels.

I'm not looking for someone to do the work for me, I'd like to learn from this, but I'd appreciate it if someone could point me in the right direction.

Thanks for your time.

2

A link to the flow meter would have been helpful but most use pulses, the faster the flow the faster the pulses. If so then you need to count the number of pulses in a set time (or the average interval between pulses) and use this value to determine the LED colour.

3

The flow meter is the 1/2 plastic flow meter Liquid Flow Meter - Plastic 1/2 NPS Threaded : ID 828 : $9.95 : Adafruit Industries, Unique & fun DIY electronics and kits from Adafruit.

It does use pulses, and I am able to get it to show input in the serial monitor, but I don't know how to take that data read, and use it in a sketch on the LED side.