Using a juicing machine, juice the carrots and apple (you should have about 1-1/2 cups juice). Place in a measuring bowl and set aside.
Juice the blood oranges by hand (or by machine)*. You should have about 1 cup juice. Add to the measuring bowl.
Juice the lemon or lime by hand and add to the bowl. Mix juices well and serve immediately. Enjoy!
Notes
You can juice the citrus by hand or machine. If you juice it by machine, you may get some bitterness from the membrane. If you use a machine, peel the citrus first or you will get really bitter juice!