Mag Excel Exports Private Limited manufactures Magnesium Sulphate Heptahydrate with Precise pH value. Mag Excel Exports Private Limited is an ISO 9001:2000 accredited company. Magnesium Sulphate Heptahydrate with Precise pH value is a chemical compound containing magnesium, sulphur and oxygen. Magnesium Sulphate Heptahydrate with Precise pH value is generally known as Epsom salt which has been traditionally used as a component of bath salts that effectively makes the body more buoyant. The Epsom salt is also used to maintain the magnesium concentration in marine aquaria that contain large amount of stony corals as it is slowly depleted in their calcification process.