yellow water means salt build up this is what i do, place your pots in a tub or something that fits the whole pot and fill the tub right to the rim of the pot without water going into the top soil and let it sit 10-15min the water will seep through the bottom hole and get the soil very very wet.

then pull her out and let the water run off and pour a gallon of clean water through her and she will be cleaned out.

another easier method is taking 2-3 gallons of water and pouring it through until she runs cleans i like my method better it gets everything out