FWIW (and not part of my “idea” above):
A 90 oz. Palmolive dish detergent container will screw into a female garden hose end and seal reasonably well, it appears. (The soda bottle did not work / leaked badly, forcibly screwed into a female hose end.)
Anyway, it looks like I can cut the Palmolive container to make a good size funnel to securely connect to a short section of garden hose. A cut up milk jug could function as a cover to keep leaves and such out.
Yeah, I know, more hillbilly engineering, but we are on a very tight budget here, since COVID-19...
“hillbilly engineering”
Most things on this farm are held together with orange baler twine until they can be fixed properly. I’ve even made a quick dog leash from it when needed, LOL!