We are in the process of draining and re filling our 20000 gal..I could not control the green alga and I thinking of trying the BBB method . I tried to post on the other thread for new people and it said it was closed...I would like to know how to start I normally add soda ash mixed with water when the pool is filled is that the same as borax???... And can I still just add Soda Ash instead?? Also is there anything I add while filling? Can I add the bleach/liquid chlorine as it is filling?