We manage a 40 acre wildlife area of the Texas Hill Country in the Edwards Plateau at about 3030 ft above sea level. The region is notable for its karst topography and tall rugged hills of limestone. The terrain throughout the region is punctuated by a thin layer of topsoil and a large number of exposed rocks and boulders, making the region very dry and prone to flash flooding. Native vegetation in the region includes various yucca, prickly pear cactus, native grasses and wildflowers. The predominant trees in the region are Ashe Juniper, Shin Oak and Texas Live Oak. Soil is alkaline consisting of caliche and clay.
Sometimes dandruff is caused by dry skin on the scalp. Are you sure it is dandruff and not dry skin? and those treatments you used are not for dry skin.
As Ali suggested it could be your water.
My water is alkaline and causes dry skin.
Or it might be the brand of shampoo. Try one for dry skin or try going pooless (without shampoo) and using bottled water.
