I think it has something to do with the grounding . With out proper grounding this can cause bluing . But how do you maintain the problem ?
No, the water in a toilet does not spin one way in the northern hemisphere and spin the opposite direction in the southern hemisphere. The spin of the water in a toilet is determined by the shape of the toilet bowl and the flush system, not by the direction of the Earth's rotation. In a toilet, the water is flushed by a flushing mechanism. This flushing mechanism is usually activated by pushing a lever or pushing a button, and it causes water to be released from the tank into the bowl. The shape of the toilet bowl, as well as the type of flushing mechanism, determines how the water will move once it enters the bowl. When the toilet is flushed, the water quickly fills the bowl and then begins to swirl around. The force of the swirling water will cause it to push against the sides of the bowl and create a whirlpool effect. As the water circles around the bowl, the shape of the bowl determines the direction in which the water will spin. The water will usually spin in a clockwise direction in the northern hemisphere and in a counterclockwise direction in the southern hemisphere. The spin of the water in a toilet is determined by the shape of the toilet bowl and the type of flushing mechanism, not by the direction of the Earth's rotation. The shape of the bowl and the type of flush system will determine the direction in which the water will spin, regardless of which hemisphere the toilet is located in.
2" or 3" integral trap built into toilet bowl.
clay used in making the porcelain bowl or the trace minerals that are in the water in the toilet bow.
Not the bowl, the tank
You would need to pour the water into the bowl.
I have lived in many places around the world, and have never seen water turn grey is a toilet bowl. I suspect this is a bogus question. Avraham HanadariANS 2 -this MAY happen if the toilet is on a well system and there's lots of fine sediment in the water. - Otherwise, yes, a bogus question.
Under what circumstance? New toilet, when you turn the water on, water goes down the overflow tube to fill the bowl. You don't have to flush it the first time to fill the bowl.
NO.
You hold them or get clean water for them
On some toilets you DO get water from front of bowl, it's all a matter of design.
clay used in making the porcelain bowl or the trace minerals that are in the water in the toilet bow.
It will not hurt the bowl, but there is some evaporation and over time the dissolved minerals and salts in the urine will form a ring around the bowl at the water line. Any toilet cleaner will remove this.