Weight of Salt Water in a Marine Aquarium

Ever wondered how heavy salt water actually is, or have heard the myths of salt water weighing up to 2.2 times fresh water? well it may well weigh that much in the dead sea, but that's no good for a typical marine aquarium environment.

When adding salt to water you add the following quantities of each product per 100 grams of water;

Sodium Chloride = 2.721g
Magnesium Chloride = 0.381g
Magnesium Sulfate = 0.166g
Calcium Sulfate = 0.126g
Potassium Sulfate = 0.086g
Calcium Carbonate = 0.012g
Magnesium Bromide = 0.008g

Which equates to 3.5 grams or 35 grams per litre! don't believe me? Have a look at a box of salt that makes marine quality salt water, now divide the weight of the product by the capacity that it makes up. -- 35 Grams Per litre.