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Humboldt HNS405 Sea Mag 32-ounce Fertilizer

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ITEM# 13991002
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ITEM#: 13991002

Sea Mag is a magnesium additive formulated to increase plant and flower growth. Sea Mag supplies magnesium, nitrogen, potassium, phosphorous and humic acid, preventing potential deficiencies. Sea Mag is great in foliar sprays. Humboldt Nutrients Sea Mag was designed in Humboldt County to be a powerful additive for hydroponics and all growing mediums. Sea Mag may be utilized for any type of vegetable, flower or herb. Sea Mag is loaded with vital elements which help control cell division, cell growth, cell differentiation and various internal processes. Sea Mag can be used to supplement magnesium and to increase plant growth. Sea Mag supplies crucial elements that plants require, preventing and correcting potential nutrient deficiencies. Sea Mag has been formulated by the Humboldt Nutrients chemists to have the beneficial nutrient ratios that plants require at specific times during their growing and flowering cycles. Using Sea Mag in addition to our complete nutrient feeding schedules can provide excellent flower production, heavy yields and high quality fruits.

  • Materials: Fertilizer
  • Capacity: 32 ounces
  • Instructions Included
  • Dimensions: 3 inches high x 7.5 inches wide x 5 inches deep

Due to the nature of this product we do not accept returns.


Type Fertilizers
Dimensions 7.5in L x 5in W x 3in H
Model Number HNS405
Country of Origin United States

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Our standard shipping method is ground shipping. We also offer expedited shipping for most items. Your final shipping cost and estimated delivery timeframe will be available at checkout.
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Standard Return Policy:

Items must be returned in new or unused condition and contain all original materials included with the shipment. More Details

FINAL SALE EXCLUSION: Items marked as FINAL SALE are not returnable unless the problem you experience is the result of our error.

For your protection, all orders are screened for security purposes. If your order is selected for review, our Loss Prevention Team may contact you by phone or email. There may be a two business day delay to process your order.

** Most Oversize orders are delivered within 1-4 weeks. Some orders may take 6 weeks to be delivered.