I built a vacation plant waterer with some tubing, 3d-printed heads, submersible pumps and an Arduino. For a longer trip, I needed a source of water that I could pump from.
I realized the toilet tank is self-refilling because of the float valve and won't overflow . So clean it out and a good place to pump my submersible pumps.
FYI you shouldn't use anything other than DI water in humidifiers. Using tap water can cause bacterial/fungal buildup and emits harmful particulates into the air.
The risk of bacterial infection is overblown. But you still don't want to use tap water for a humidifier because you'll get limescale all around the device.
The link you’re replying to basically postulates that with tap water you are inhaling PM2.5 particles from the same chemicals that cause limescale, and as far as we know PM2.5 particles are harmful to your health in any quantity.
I realized the toilet tank is self-refilling because of the float valve and won't overflow . So clean it out and a good place to pump my submersible pumps.