You'll get better color by recycling wastepaper in the color you want. The paper industry spends millions on dyes and technology to color fiber. You get all that for free in your wastebasket. Once you start looking for color paper to recycle, your wastebasket will become a fascinating and invaluable place.
Hi t, not recommended. It ends up staining everything except it doesn't tint fibers very well. Recycle colorful wastepaper to get the color you want in your handmade paper.