Yes --- you should spread out your intake of vitamins --- one in the morning and one in the evening. If you take two at once, you're just peeing out all of the nutrients.

Yes it's a good idea to spread out the vitamins. The body will discard through the urine anything it cannot use or absorb. Also just an FYI - There are at least two ways vitamins in the urine are beneficial to your body.

1 - It's presence in the urine promotes good health in the bladder and kidneys.

2 - The nutrient may have preformed a useful function somewhere else in the body before it's excreted.