Trying my best to be patient and think about the end-goals of the project, and the baby steps I will need to take to fully learn and feeling like I own the project.

Thinking about the planning phase this is the simplified and n00b basics I wanted to get out of the brain and on paper.

Materials (have/needed):

Have:
1.) Aquarium Water Pump (seems strong enough)
2.) Old Rainbird Solenoid controlled valves (I will attempt to use these, but I am curious if the flow of the pump will be enough for these devices. I am not sure if they require certain pressure or flow rate to function properly since these are used for proper irrigation systems connected to mains - If this doesn't work then I will need to purchase solenoids, or re-purpose/modify the Rainbirds) EDIT/NOTE* These are 24VAC so now reconsidering buying 12VDC Solenoid valves instead.
3.) Arduino Mini/Teensy?
4.) Wiring/cabling
5.) Relay 120VAC rated for water pump

Needed:

1.) ***UPDATE: these are 24VAC solenoids. So now reconsidering getting small 12VDC Solenoids and a 12-VDC Wall Wart (can be salvaged somewhere...) for solenoid valves
2.) Voltage Regulator for either 3.3V or 5V depending on which Arduino I use
3.) (3) BJTs or MOSFETs - maybe (3) Diodes for flyback diode purposes (Need to investigate if I actually do need it for this situation

Photographed below is also a simple logic flow of how the pump will distribute water to different zones. For the sake of simplicity, the piping will just go to buckets for now that I can hand carry to plants.

End-Goals and Ideas:

1.) Gather Metrics:
How much water was generated today? Month? Year?
What is the water level in the reservoir/collector?
2.) Programmable Watering Times (GUI/Interactive)
3.) More stuff that I cannot think about right now because information overload from other stuff.