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Information source: http://www.nature-aquarium.com/order.htm

Nutrients Necessary for Healthy Plant Growth

There are only 13 essential nutrients

There are only 13 mineral nutrients needed for plants to grow. The nutrients
are divided into two groups: macro-nutrients and micro-nutrients.

Macronutrients

As the name suggests, macro-nutrients are absorbed by the plants in higher
quantities and these are: nitrogen (N), phosphorus (P), potassium (K), calcium
(Ca), magnesium (Mg) and Iron (Fe). Whilst these nutrients are present in PUB
water, they are present only in small quantities insufficient to promote and
sustain healthy plant growth. Indeed, PUB water is rather soft lacking in
minerals such as calcium (Ca), magnesium (Mg).

Nitrogen (N) : An essential part of all living cells. Aquatic plants get
their nitrogen supply in the form of nitrate. And nitrate is obtained from the
conversion of ammonia waste of fishes. This conversion is achieved by the
biological colonies of denitrying bacterial found in the filters. Nitrate is
usually abundant in planted aquariums with fishes and no addition is thus
required.

Potassium (K) : plants require large amounts of potassium for growth. It is
required in protein synthesis, and helps plants to metabolize iron. Need to be
added in sufficient quantities to replenish the high absorption rates. My
Nature Aquarium' s Potassium Sulphate (K2SO4) is an ideal source.

Phosphorus (P) : helps convert light into sugars that the plants use to feed. However, excess phosphorus will inevitably contribute to algae growth.
Present in adequate amounts in PUB water, and by the addition of fish food to
the tank. Never, never add phosphorus or posphates to the tank.

Iron (Fe) : absolutely essential for plant growth. Must be present for the
manufacture of chlorophyll. Without adequate iron (about 0.1 to 0.5 ppm),
plants will yellow and fail to produce the lush green or bright red color.
Ideal source is My Nature Aquarium' s Iron & Trace Elements solution.

Magnesium (Mg) : An integral component of chlorophyll. Essential to the
transport of iron in the plant. Lacking in soft water such as PUB water. My
Nature Aquarium's MgSO4 crystals will replenish the levels required for
healthy plant growth.

Calcium (Ca) : a component of cell wall structure. Helps provide strength to
the plant, and helps transport other nutrients throughout the plant. Ideal
source is My Nature Aquarium's Calcium Carbonate tablets.

Micro-nutrients

Micro-nutrients are required by the plants in smaller amounts. The
micro-nutrients are: sulphur (S), boron (B), copper (Cu), chloride (Cl),
manganese (Mn), molybdenum (Mo), and zinc (Zn).

All these micro-nutrients are available in the optimal amounts in My Nature
Aquarium's Iron & Trace Elements solution.

Sulfur (S) : Helps in chlorophyll production, and essential for healthy root
growth. Stimulates rapid plant growth.

Boron (B): Essential for the regulation of other nutrients. Helps the plant
produce sugars and starches. Very small amounts required.

Copper (Cu) : Essential for the plant to reproduce. Helps stimulate the
production of proteins.

Chloride (Cl) : Plays a role in plant metabolization of other nutrients.
Present in chlorinated water.

Manganese (Mn) : important nutrient that helps the plant digest starches and
nitrogen, thus helps the plant to use other minerals.

Molybdenum (Mo) : assists the plant to metabolize nitrogen. Very tiny amounts
required to maintain plant health.

Zinc (Zn) : Essential for carbohydrate metabolization. Helps regulate plant
growth.