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Thrive Aquatics 3 Magnesium

Sku: TH-3

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Thrive Aquatics 3 Magnesium

Sku: TH-3

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This product is harmful if ingested. If swallowed: give water, get medical attention. May cause eye or skin irritation. If in eyes, flush with water for 15 minutes, get medical attention. If on skin, wash thoroughly with water. Keep from freezing. Keep out of the reach of children. Do not use this bottle for drinking water. 

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Product Name Price
Thrive Aquatics 3 Magnesium Refill 20.3oz (600ml)
(Usually Ships in 4 - 5 Business Days After Submission of Order)

Regular Price: $12.95

Special Price $10.95



Thrive Magnesium is designed to increase Magnesium and correct ionic imbalances in your marine aquarium. The chemical management of salt water, reef aquariums is a delicate balance. The Thrive products and Thrive Analytics were created to help you simply assess and adjust the balance of your salt water aquarium system.

High Concentrations:

Thrive Magnesium is a saturated solution of magnesium chloride and magnesium sulphate. This means you won’t find this blend of magnesium any stronger. 


Determine the magnesium level in the aquarium before supplementing. For best results test your aquarium water using a quality test kit like the Salifert Mg Test Kit or Elos Mg Test Kit.  
  • Find the current Magnesium value.
  • Add 1 ml per 5 gallons daily until the target magnesium is reached.  
  • Dose daily as needed maintain magnesium at 1250 to 1370 ppm.
  • Dosing without testing is not recommended. 
Each ml of Magnesium will increase the magnesium in 1 gallon of water by 32.6 ppm. Add magnesium at the maximum rate of 2 ml per 1 gallon daily until target is reached. Then dose weekly or as needed. 
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Product Specs


Manufacturer Thrive


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