I've used it before to go from black to blond, and it worked beautifully. When I did that though, the black dye had just been put on my hair and I used the developer that comes with it. Now I'm wanting to go back to brown, and I was wondering if it would sufficiently remove this black dye (that I applied in October) if I used it and just mixed it with water. All I'm wanting to do is go back to a dark-medium brown, and I don't need to go super light. Some of my hair isn't in the best condition, and that it why I want to try to avoid using the developer that comes with it..

Any help?

So you need to lift the black a bit so you can dye it brown?

I haven't used Color Zap but if it can lift 2 or 3 levels with just water you can go dark brown. If you need a medium brown you might need to mix it stronger. The only way to know for sure is to do a strand test.

i use and love color zap. i used the full blown mixture (both packets and the developer) on my jet black hair. it took it to a reddish blonde. which was amazing. i had it on for 2 hours. it dosent use much bleach so it should be alright for your hair. maybe try he water method if you are wanting a light lift.