Thanks, mal. I picked up a "Claber Oasis" thingamajig. It's a 6+ gallon bucket with a timer that runs on a 9v battery. Gravity feed and will probably get the job done if the plants don't consume much more than they already are. Looks like the issue on this might be the feed rate (not so much the capacity).

I just split a gallon between my two plants and got zero runoff (last watered 4 days ago). The girls are getting thirsty.