1, thoroughly clean the rotten roots, cut off the yellow leaves from the petiole, and cut off 3-5 cm from the roots according to personal experience.
2. It is best to disinfect the roots. You can disinfect the roots of plants with carbendazim or hymexazol. Alcohol is ok, but plants will be poisoned if it is not handled properly. . . If you don't have these things, just put them in a sunny place for a while, 2 or 3 hours, all morning, whatever. Don't be afraid of them withering, just wait until you see the rotten roots dry.
3. Wash the vase thoroughly, add clean water and dry it in the sun for 2 hours. The water used for hydroponics should not be tap water directly. It's best to dry it for a while to let the chlorine in tap water evaporate, and it's cold now, and the water temperature is the same as room temperature, otherwise it's not good to stimulate the roots.