Out side Hydroponics

[GardenState]

So I'm new to this a bit, this winter I have had successes with both dwc and ebb and flow lettuce. I'm busy getting stuff started for the outside garden but I have been thinking about doing some hydro outdoors.

It sounds like nft is the preferred outdoor technique using some sort of pipe or gutter.
My concerns are the res and the very difficult task of burying anything without a backhoe.
And power failure leading to the quick death of plants.

How do you size the res? How many gallons per plant.

I also have a problem with very high Ph (8) water. So the res can not easily be topped off without PH correction. So if away for a few days there has to be enough water. Or is there some sort of cheap way to auto correct this if I use a float valve?

We loose power a lot, while I do have a generator if I'm not home its not going to get started.

Anyone have any luck with 12 volt dc pumps? I was think a large battery and a charger connected, so when to power goes out the pump keeps running. I might even consider a solar panel if I can find one cheep.

Also can you use one res for multiple plant types? Is there a happy medium for the food. Something every plant will like.