Hey! Thanks for your interest in the project.
Schematics are available in the Eagle files (as well as my PCB layouts) - available for download from my OneDrive:
https://onedrive.liv...FCDC3DBD261!366
I am not doing anything with solenoids / valves (don't really need to) but I turn the pumps on & off with a pair of 10A SSRs from Crydom. They are probably overkill, but better safe than sorry, as far as I am concerned.
Hope that helps!