(Replying to Praus in regards to my earlier post.)
The water in my toilet is definitely not blue because it's reflecting the sky--I don't have a skylight in my bathroom, and I keep the blinds on the window closed (I'm not into drawing an audience while in the bathroom.)
I had thought this would be kind of obvious since I mentioned cleaning the toilet... But apparently I overestimated the given explanation. The water in my toilet is blue because, ta da... the type of cleaner I use happens to be blue. Deep, scientific explanation, I know.
So yes, if I'm wanting to switch it up, I could certainly use a red (or chartreuse, or seafoam, or hot pink) colored cleanser.
Now, to keep this thread on-topic... I suppose I can say that my mind is going to a happy, calming place just by thinking of the bright blue water in my freshly-scrubbed, Sno-Bowled toilets...