Fluval Sea Magnesium Aquarium Water Conditioner, 8-oz bottle

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About This Item

Details

  • Concentrated, magnesium-boosting compound effectively elevates magnesium levels in your aquarium
  • Supports optimal pH and strong coral growth as well as helps prevent calcium precipitation which can cloud water, coat aquarium walls and clog pumps
  • Contains high quality and ultra pure magnesium chloride, free of unwanted contaminates
  • Does not contain gluconates, nitrates, or phosphates
  • Offsets ongoing depletion of magnesium caused by coral absorption

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4.6
Rated 4.6 out of 5 stars
5 Ratings
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3 Customer Reviews

Rated 5 out of 5 stars
By Edison on Nov 26, 2025

Good supplement

Great for keeping my magnesium up, since coralline algae keeps eating it all

Great for keeping my magnesium up, since coralline algae keeps eating it all

Rated 3 out of 5 stars
By Brandon on Aug 18, 2025

good product just weak

i wouldnt recommend for bigger tanks. one dose is the entire bottle for me.

i wouldnt recommend for bigger tanks. one dose is the entire bottle for me.

Rated 5 out of 5 stars
By Al on Mar 15, 2024

Grow Corals Grow

The product was reasonably priced and arrived before expected. Magnesium is one of the keys to beautiful corals and Fluval has the purity of a clean ocean. Well

The product was reasonably priced and arrived before expected. Magnesium is one of the keys to beautiful corals and Fluval has the purity of a clean ocean. Well worth the purchase if you want strong, beautiful corals!!