(Add one level measuring spoon of Tropic Marin® Reef Actif to 500 litres/132 US gallons of aquarium water each week. Stir the powder into a small amount of aquarium water and then add it to the aquarium to distribute it as finely as possible.
Maximum dosage: One measuring spoon per 500 litres/132 US gallons of aquarium water three times a week.)
(Tropic Marin® Reef Actif can be used with all other products of the Tropic Marin® Bio-Actif-System with no concern for overdosing of organic substances.)
I copied & pasted directions from corporate website And will start at I level teaspoon for 150G system at 3 times a week. On 5 year old tank as it is limping along.
My 75G 25 year mature tank will get half that dosage three times a week. Because of the diversity of filter feeders already in this tank, I will continue dosing an 8 ounce cup of phytoplankton three times a week. I consider phyto a type of carbon dosing and dose during daylight hours so that inorganic nutrients are absorbed during daylight until phyto is consumed by filter feeders.
PS: Tropic Marine USA preferred dealers.
http://www.tropicmarin-usa.com/preferred-dealers.html