Hi Rufio,
All the mags and detox/ healthy eating literature I've read (many!!!) always suggest either plain, mineral or spring water or flavouring it with slices of lemon/orange or lime is the best for you.... I prefer all three, with ice. I think it has something to do with the chemicals in the juice itself... either way, it certainly sounds pretty bad that you're drinking 2litres of diluted juice and its making your pee that colour... seems as though it hasn't gone through your system properly!!
Anyway, take it easy. XXX