I’ve been using natron (backing powder) for a couple of years now twice a week. I had no need for shampoo ever since. You just mix one tablespoon natron with water in a cup and are good to go. To even out the ph of the hair use a teespoon of cider vinegar mixed with water in a one of those spray cans used to water flowers. Works well for children as well, as none of this burns your eyes. As a side effect I stopped getting red eyes from using shampoo.