I'll chime in on what Drew wrote. Watercolour paints can be excellent, but you do get what you pay for. Cheap "student" paints are often full of chalk, starch, and a mish-mash of pigments/dyes. Look for paints containing single pigments, not blends. Dry pigments can be a real pain in the *** to disperse without specialty wetting agents. The same wetting agents however can render the gelatin mixture very fluid and tricky to coat - though one dried, they behave normally. Fortunately, tubes of watercolour paints are much more reliable and consistent than they were in the past. Note also that a pigment or paint that contains "UV protectants" is going to wreak havoc with carbon prints.