First of all I would not use an outside feeder. You can place it at a distance, but it could still enhance a robbing frenzy. I would go with some type of inside feeder, if you do not want to drill a hole in the top cover and use that type of out side feeder. Just don't use small plastic bottles.
I have used pint and quart canning jars. The old 2 liter glass cola abd beer bottles are good, if you can find some.
If you go with the one gal or two gal bucket. Make sure you fill it as full as possible. Have an extra bucket to hold it over as you invert it to catch the spill. Hold it there till it stops letting the excess off
before putting it in place, you don't want to drown your bees with what you are trying to feed them.
If you have a good strong nectar flow don't even feed.
My put :)doak