Dyi ato
 

Take a look at this and see if it you think it would work? It's a 5 Gal bucket that has only been used a could times to make some home brew hard apple cider. So all it has had in it is Apple cider, sugar, yeast, and Star San which is a sanitizer. The hose is a food quality hose that has had the same product thru it. I was thinking cleaning it all with vinegar then using it as a 4-5 Gal gravity feed ATO system. Do y'all this this would be ok??

Yup, should work with a lid

I actually kinda do the same for my QT. I have a 5 gallon food safe bucket from lowes. I drilled a hole and screwed in a 1/4 push by 1/2 threaded fitting. I connected that to a 1/4 push valve and then to an eshopps float.

As long as you are aware that evaporation rates change over time and that the valve on there is unlikely to maintain a consistent drip rate so you will likely need to monitor/adjust it then go for it..