Update:
I have decided to go the MOSFET.I’ve used some other posts as a guide specifially these;
https://community.particle.io/t/n-channel-mosfet/
https://community.particle.io/t/controlling-fan-speed-with-photon-and-fet-transistor
Now i have a simple circuit sketched in frizting which ill attach now;
I haven’t wired it up yet as i’m still waiting for some parts but i wanted to post it here for it to be sanity checked and critiqued. I plan on having more than one of these valves ( and other components) connected to the power supply, and i still don’t know how to do that as my power supply only has two terminals. Do i run one to a power rail and just use the LVT’s off the rail?
I hope this post helps more than just me understand the underlying principals.
Thanks in advance.