Mikvaos 7:3-4

Mikvaos 7:3

If one rinsed baskets of olives or of grapes in a mikvah and they changed its color, the mikvah remains valid. Rabbi Yosi says that dyed water renders a mikvah invalid in three log, but not by changing its color. If wine or olive juice fell into a mikvah and changed its color, it is invalidated. In order to re-validate it, one waits until rain falls and the color reverts to that of water. If the mikvah contained 40 seah, one may carry water on his shoulder and put it in until the color reverts to that of water.

Mikvaos 7:4

Let’s say that wine or olive juice fell into a mikvah and changed the color of some of the water. If the mikvah no longer contains 40 seah the color of water, one may not immerse in it.