Making a manual watering system

Lets say you had a lot of plants, and wanted to water all of them without having to make up lots of 1 gallon batches of PH adjusted nute solution. I'm thinking of just using a 100 gallon rubbermaid with a pump and a piece of tubing. You could let it run with the tubing in the reservoir to mix everything. Problem is, you can start and stop it without unplugging the pump.

I need something like a garden hose nozzle that can connect to 1/2 in or 3/8 tubing and run off a mag drive pump. I say mag drive because I think you can burn out a direct drive pump if you block the water flow.

Anyone know how to set this up?

Hmm sounds like your over complicating things a little. I have a similar set up with a sunleaves 138 gph submersible pump and a 20 gallon rubbermaid. I control this with a simple digital timer i run for 2 minutes 2x per day at a time. All you need is....

100 gallon rubbermaid
subermersible pump
digital timer
air divider
tubing
bubblers/soaker hose or what ever you want to use

I wasn't really looking to automate the whole thing, just suck water out of the reservoir when needed. You kind of got me thinking though - full auto would be nice, though you'd need a way to switch between the nute res and the plain water res.