NUALGI

http://nualgiaquarium.com/about-us/faqs/
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So Nualgi contains copper, isn’t that harmful to marine life?
The relationship between copper in the organism and in its environment is complex as it depends on the particular organism and on the bioavailability of copper. Copper is an essential mineral for humans, plants and organisms. For humans, it is required by the body for bone and connective tissue production, and for coding specific enzymes that range in function from eliminating free radicals to producing melanin. A deficiency in copper can lead to osteoporosis, joint pain, lowered immunity etc.
According to University of Florida research, recommended Cu2+ concentrations of 0.15–0.20 mg/L, free copper is toxic to a number of organisms that are pathogens of fish. Some species of fish are highly sensitive to copper and will die even at concentrations below therapeutic levels (i.e., less than 0.15 mg/L free copper). <b>Copper concentration in Nualgi is at 0.0005mg per L which is further diluted in the tank by a factor of 100 dosing 1ml in 30 gallons.</b>
Furthermore, Nualgi is a nano scale formulation. As indicated elsewhere in this FAQ, nano particles have different properties to coarse particles. This small amount of copper is required for the diatom bloom and is considered safe for aquatic life. Two of our trialists mistakenly dosed the entire 12 week dose at once. No impact was seen on the aquatic life in their tank.
Because of its nanosize, Nualgi is able to pervade very small spaces in the subsurface and remain suspended in water. This allows particles to travel farther and dissipate quicker than coarse particles thereby increasing the bioavailability of the nutrients for easy absorption. The iron and other micronutrients in nano form cannot precipitate out or gel in the water as it happens when they are added directly as salts