HI so, hi. So, I live in a house where the three of us color our hair on a regular basis. Our tub doesn't drain properly (we're working on it), but this means there's often some kind of hair color residue disgustingness in the tub. Mine is by far the worst offender in the Hair Color Wars, because I dye it blue-black. If we could get the tub to drain, it would be better, but in the meantime, do you have any ideas how we could keep the problem down between bathroom unfuckings?
Comet and/or Magic Erasers. I dye my hair all sorts of colors, and if the staining is happening during the coloring process, try a preventive layer of Comet before you rinse (wear flip-flops, though). And, yes, fix the drain problem.