You can also over-complicate your post. Promix as no compost in it, it's dry. And watering with ro washes the soil anyway. And if you want to wait for chlorine to evaporate that's up to you. But it wont make the water less contaminated by the chemical sediments. and water with a ph of 7.9 and 750ppm and bacteria, sure hope you like being sick and good luck fighting cancers and diseases in your future.Drinking limescale can cause arthritis .Joint pain mans best friend!