Density of these fluids is maintained with salts. A variety of salts, NaCl, KCl, NaBr, Na-formate and K-formate can be used in the fluid to salt saturation. In addition, CaCl 2 , K-acetate, freshwater, seawater and field brines can be used for density. The salt concentrations can be adjusted for density and/or inhibition. In addition, liquid shale hydration suppressants, either amphoteric or cationic, can be used to control inhibition levels without increasing density. Glycols may also be used in the systemto improve inhibition.