Parah 5:3-4
Parah 5:3
If a pumpkin shell was submerged in water that is unfit for sanctification, they may sanctify (i.e., mix the ashes of the cow into water) in it so long as it hasn’t been rendered ritually unclean; if it has been rendered unclean, one may not do so. Rabbi Yehoshua says that if one may sanctify in it at the beginning, let him also do so at the end; if one may not do so the end, then let him not do so at the beginning. In either case, one may not add already-sanctified water to the pumpkin shell.
Parah 5:4
Rabbi Eliezer says that a reed that was cut to hold the ashes must be immersed in a mikvah right away; Rabbi Yehoshua says that one renders it ritually unclean and then immerses it. Everyone is fit to mix the ashes into the water except a person with congenital deafness, a person lacking mental competence and a minor. Rabbi Yehuda says that a minor is qualified to do so but he disqualifies women and hermaphrodites.