I haven't specified the Arduino as I haven't decided yet,still planning at this stage. It will be a 5v though, I'd completely overlooked that I could connect to the vin/5v, mistakenly thought they'd have the same low current load as the gpio pins! Thank you!
Is there a reason you recommend connecting to the Vin and not 5v?
I'll need to do more reading on the mosfet, my electrical knowledge and understanding really is very slim (why I started doing Arduino stuff is to try and improve) making the jump from turning LEDs on and off and reading sensors to powering things is proving a challenge.