So I happen to notice that the inside of my waterer gets slimy when I refill it.
I heard from an old timer to put a few drops of bleach in the waterer I haven't done this but what's everyone's thoughts?
What type of waterer? metal, plastic, black rubber?
You are in a cold region, are you still seeing slime?
It is typical to get slime when the waterer gets hit with sunlight - or it is warm. So, then clean it out throughly with soap and water, and follow with a short soak with bleach water. This is what I have to do to the non-metal waterers in warm weather.
I have an older male neighbor and he does add a drop of bleach to his water in the warm weather to reduce/mitigate the slime. He does refresh the water every day, and he uses open buckets.
My galvanized metal waterer does not seem to be having a slime problem, so I am happy about that!