Digital pots


I have 2 HHO fuel cells that i have made for my motorbike they are controlled with a Arduino
My problem is i have 20A DC10-60V PWM HHO RC Universal Motor Speed Regulator Controller


It has a potentiometer that reads 12v and I would like to control it from my Arduinio I have looked at digital pots but they are all 5v

is there a way around this ?

That looks like a good unit but it is hard to tell from the information there if it can be controlled by a 5V Arduino. It could be as simple as "Just change resistor R1" but without access to the unit to test it I could not give you that reccomendation.

I suggest you buy a purpose-built Arduino motor shield. Adafruit has a good one and I have used a couple of the SparkFun units in the past and found them to be good too.