Low Heavy Metal Magnesium Nitrate Crystal for Hydroponic Nutrient Solution

This low heavy metal magnesium nitrate crystal is a fertilizer grade magnesium nitrate hexahydrate, Mg(NO3)2·6H2O, supplied as a free flowing white crystalline solid with a minimum assay of 98.5%. It is manufactured by nitric acid neutralization followed by controlled continuous crystallization, a route that keeps water insoluble matter below 0.05% and holds lead, arsenic and cadmium at trace levels. For growers who run closed irrigation loops, that purity profile is the practical difference between a nutrient salt that stays in solution and one that slowly loads the substrate with contaminants.

Every production lot is sampled after drying and screened for heavy metals by an independent laboratory before packing. A certificate of analysis carrying the batch number, assay, moisture and heavy metal results travels with each shipment, so an agronomist can file the data next to the crop nutrient records. Because the crystal dissolves completely at 420 g/L at 20 °C, stock tanks reach the target EC without long mixing, and drip lines, misting nozzles and fertilizer injectors stay clear through a full crop cycle.

• Low Heavy Metal Profile: lead 5 ppm max, arsenic 3 ppm max and cadmium 2 ppm max, verified batch by batch by an independent laboratory instead of a single annual sample.
• Crystal Form and Dissolution: white crystalline solid with 420 g/L solubility at 20 °C; it dissolves without residue and leaves no sediment in stock tanks.
• Production Process Control: nitric acid neutralization and continuous crystallization deliver a stable 98.5% minimum assay with water insoluble matter below 0.05%.
• Balanced Nutrient Ratio: 11% nitrate nitrogen and 15.5% water soluble magnesium oxide in one salt, so calcium free formulas stay simple.
• Low Salt Index: a lower salt index than potassium or ammonium nitrate sources reduces osmotic stress on young transplants and sensitive roots.
• Eco-friendly Composition: chlorine free, with no anti-caking filler or coating, which keeps tank residue and drainage load to a minimum.
• Storage Stability: sealed 25 kg bags remain free flowing for 24 months at ambient temperature when kept dry and ventilated.

• Hydroponic nutrient solution: supplies magnesium and nitrate nitrogen in the A tank for leafy greens, strawberries and herbs in NFT and deep water culture.
• Soilless culture: a clean magnesium source for coco coir, rockwool and perlite slabs, where residual sodium and chloride must stay low.
• Greenhouse fertigation: routine injection for tomato, pepper, cucumber and eggplant, particularly where magnesium demand peaks at fruit set.
• Foliar and root feeding: a fast correction for interveinal chlorosis in fruit trees, citrus and vines during the growing season.
• Blended water soluble fertilizer: a low heavy metal crystal base for water soluble NPK formulations and specialty crop programs.

Why choose a low heavy metal magnesium nitrate crystal instead of standard fertilizer grade?

Standard fertilizer grade material is normally tested once per season. This low heavy metal magnesium nitrate crystal is released only after a lot by lot heavy metal screen, which matters in closed systems where trace elements accumulate in the substrate and in the drainage water over several crops.

How is this crystal dosed in a hydroponic nutrient solution?

A typical working concentration is 0.3 to 0.6 g per litre of final solution, adjusted to the magnesium target of the crop recipe. Because the crystal dissolves at 420 g/L, a concentrated stock of 100 g/L can be prepared directly in the A tank without heating or prolonged agitation.

Will the crystal stay in solution in a soilless culture system?

Yes. Water insoluble matter stays below 0.05%, so the crystal does not leave sediment in drippers, misting lines or return channels. In soilless culture the material is normally combined with calcium nitrate in separate tanks to avoid precipitation.

What documentation ships with each batch?

Each shipment includes a certificate of analysis showing the batch number, assay, moisture, pH, insoluble matter and heavy metal results, together with the safety data sheet and a loading list that matches the bag numbers on the pallet.

How should the product be stored before use?

Keep the bags sealed in a cool, dry and well ventilated warehouse, away from combustible materials and reducing agents. Magnesium nitrate is hygroscopic, so an opened bag should be closed again after dosing to keep the crystal free flowing.

The crystal is packed in 25 kg PP woven bags with an inner PE liner, 40 bags per pallet, and a 1000 kg jumbo bag is available for blending plants. Bags are marked with the batch number, production date and net weight for traceability, and private label printing can be arranged for regular programs. Our plant works under ISO 9001:2015, keeps a retained sample of every lot for 24 months, and supports buyers with third party inspection, pre-shipment sampling and technical advice on nutrient recipes for hydroponic nutrient solution and soilless culture programs.