Same 😂

Same!

I have not a clue but... there are videos on how to distill water at home & you can even make a system for reverse osmosis which is more effective that a water distiller. Hope this helps.

If you don't want to read my long detailed instructions the answer simply is...no...you do not need the filter for it to work properly as it's own water dispensing system (I describe how to do it all but if you want a visual example then just do what the man in the beginning of the video does to fill it basically). I personally was worried about that too because I feel the filter might get gross in an animal water dish (like all slimy and possibly moldy but I could be wrong and I'm just mentioning why I didn't want to use it). But I found it is possible to use this water bowl without the filter and it not spilling a drop. I do everything upside down in preparation of it (I don't disconnect it like the man in the video does where it's right side up). I fill the jug part with water to the very top upside down and keep it that way while I take the bowl part and reconnect it upside down onto the jug part with the water in it (make sure to connect it properly or it will all fall apart and spill). I lift it off the floor (still upside down) in between my hands/palms firmly then I flip it over quickly and set it on the floor. So it is all in how you fill/connect it and disconnect it/refill. So you do this the same way when you refill it whether it has some water left in it or not but always do it upside down if it has water in it. Oh and be careful not to "swing flip" it or it will slosh. It takes some practice but I haven't had a drop of water on my floor yet from filling it since I've figured it out. It's a great system for pets that need tons of water like my three kittens.

Magic

The water can't flow freely because there is no way for the air to freely flow into the bottle. The water will always (until the bottle is depleted) sit right at the level of the bottom of the opening. Whenever the pet drinks some of the water it lowers the water level in the bowl slightly, this creates a tiny space through which air can enter the bottle. The air can displace a small amount of the water, allowing it to flow into the bowl. The air doesn't "know" that it is supposed to discretely dive into the bowl of water, swim around and up under the bottle and enter the bottle neck. If it did, it would behave as you prefer.