Regarding how much borax to put in a bath:
One cup of borox should do nicely. It does clean very well and soaking your hair in it will leave it soft. I would highly recommend showering afterwards. It will leave you feeling rejuvenated and full of energy. Ahhh like brand new. I soak 10 to 15 minutes. Thank God for boron. God bless you.
For those having issues ingesting Borax I would suggest bathing. I had major healing bathing using various mineral salts in a hot bath for an hour a day for six weeks. I had been diagnosed with lyme and associated co infections including candida and cleared most if not all symptoms using bath salts, citrus (vit. C) and hydrogen peroxide in combination topically. I used Borax, Epsom, sea salts and dead sea salts together. I would also add half a bottle of Hydrogen peroxide and scrub my skin with citrus. I used about 4 cups total salt per bath. Soaking the neck and thyroid seems important and I cleared lumps around my thyroid and all sorts of skin anomalies. Whenever I feel sick again from environmental toxins and parasites I just take a few baths a week and it clears my system. I was sick for 8 years and tried western and non-traditional treatments and nothing worked like this bath formula. I never ate borax but did increase ingesting mineral salts, Vitamin C and MSM. I also like to put Borax in my work boots. I noticed a detox from this.