Picture update on the system I use
That pic is the bucket that contains the float valve. The waterlines branch out from this bucket to all other buckets. I removed the lid to show the inside. The valve sets the water level of all the buckets that are hooked up to it, if they set on a level surface.
I used some 2×4 precuts to make them level by building a rack. It’s easier than leveling the ground.
There is some algae backing up into the bucket. We have had a lot of rain lately, and the overflow from the planted buckets flows back into this supply bucket thru 1/4″ clear hose and flows out thru a hole drilled into this bucket just above the waterline. This hose is where the algae is coming from, since light penetrates the hose. If I used black hose, this wouldn’t be a problem because algae requires sunlight to grow.
Here is the system. I used heavy duty trash bags underneath in order to control weeds.
The empty buckets were zucchini, after vine borers got to them. I replanted and hope to get something out of them.
I also disconnected the pepper plants, because they were getting too much water. I’ll water them by hand from now on.
I like this system. I get good growth and don’t have to worry about watering the containers. Tomatoes use a lot of water, and you don’t want them to go without, even for a short period of time. When I used just the buckets last year, I’d have to water them at least 3 times a day, and even that wasn’t enough to keep them properly watered.