Exaxol Fresh Water Standard, Very Soft, 25.9 ppm TDS, (10-13 mg/L as CaCO3)

Fresh Water Standard, Very Soft (10-13 mg/L as CaCO3) by Exaxol, catalog numbers T70401-1 and T70401-4, is a synthetic very soft fresh water standard with about 25.9 ppm TDS and hardness of 10–13 mg/L as CaCO₃, matching EPA very soft reconstituted water. Available in 1 L and 4 L from MBP, a registered vendor to many research institutes across the USA.