--- product_id: 12258123 title: "Brightwell Aquatics Magnesion Ionic Magnesium for Reef Aquariums, 250 ml" brand: "brightwell aquatics" price: "€ 23.35" currency: EUR in_stock: true reviews_count: 9 category: "Brightwell Aquatics" url: https://www.desertcart.hr/products/12258123-brightwell-aquatics-magnesion-ionic-magnesium-for-reef-aquariums-250-ml store_origin: HR region: Croatia --- # 250 ml high-concentration ionic magnesium Precise dosing for 1,290-1,320 ppm Mg balance Premium American-made quality Brightwell Aquatics Magnesion Ionic Magnesium for Reef Aquariums, 250 ml **Brand:** brightwell aquatics **Price:** € 23.35 **Availability:** ✅ In Stock ## Summary > 🌊 Elevate your reef’s glow with ionic magnesium mastery! ## Quick Answers - **What is this?** Brightwell Aquatics Magnesion Ionic Magnesium for Reef Aquariums, 250 ml by brightwell aquatics - **How much does it cost?** € 23.35 with free shipping - **Is it available?** Yes, in stock and ready to ship - **Where can I buy it?** [www.desertcart.hr](https://www.desertcart.hr/products/12258123-brightwell-aquatics-magnesion-ionic-magnesium-for-reef-aquariums-250-ml) ## Best For - brightwell aquatics enthusiasts ## Why This Product - Trusted brightwell aquatics brand quality - Free international shipping included - Worldwide delivery with tracking - 15-day hassle-free returns ## Key Features - • **Pure Ionic Power:** Ultra-concentrated magnesium formula ensures reef vitality without unwanted organics. - • **Precision Reef Care:** Tailored dosing maintains optimal magnesium levels to stabilize calcium and carbonate balance. - • **Reef-Building Essential:** Supports aragonite formation, the backbone of healthy coral and clam skeletons. - • **Crystal Clear Confidence:** Leaves no residue or cloudiness, keeping your aquarium pristine and vibrant. - • **Trusted American Excellence:** Scientifically formulated and proudly made in the USA for consistent, reliable results. ## Overview Brightwell Aquatics Magnesion is a 250 ml high-concentration ionic magnesium liquid designed to maintain ideal magnesium levels (1,290-1,320 ppm) in reef aquariums. Free from organic additives, it supports coral and clam skeletal growth by promoting aragonite formation, stabilizes calcium and carbonate balance, and treats up to 1,000 gallons per bottle. Made in the USA with scientifically backed purity, it ensures precise dosing and crystal-clear water for thriving reef ecosystems. ## Description Brightwell Aquatics MAG250 Magnesion Liquid Salt Water Conditioner Elevate your reef aquarium's health with Brightwell Aquatics magnesium solution, a highly concentrated ionic compound formulated by marine scientists for aquarium water treatment. This aquarium water conditioner provides a potent dose of magnesium, regulating the delicate balance between calcium and carbonates in aquarium water. Crucial for reef-building organisms, magnesium is a key component of aragonite, the mineral responsible for skeletal material formation in corals, clams, and allies. Outclassing competitors, our solution is stronger, ensuring unparalleled effectiveness. It contains no unwanted organics like EDTA, gluconate, or polygluconate, offering a pure and focused solution. With a magnesium concentration recommendation of 1,290-1,320 ppm, achieve the perfect balance for immediate positive results in calcium supplementation. Understanding the unique requirements of each aquarium, our solution allows for precise dosing tailored to your setup's magnesium uptake rate. We recommend using a quality salt mix for stable seawater parameters, providing a robust ionic foundation. Trust in Brightwell Aquatics' commitment to purity—our liquid water care supplements are made with purified water and high-purity materials. Formulated based on empirical data, our solutions prioritize observation and measurement over theory, ensuring a precise and effective formula for your aquarium's success. FEATURES AT A GLANCE Super strong solution to maintain a balance between calcium and carbonates No unwanted organic material Provides a potent dose of magnesium Developed based on empirical data, prioritizing observation and measurement Formulated utilizing extensive data compiled by microbiologists AMERICAN-MADE EXCELLENCE Trust in the quality and excellence of Brightwell Aquatics, an industry-leading brand committed to providing innovative and scientifically backed aquatic care products. Made in the USA, we consistently strive to deliver advanced superior quality solutions to elevate the vibrancy and health of your aquarium. Review: Nice product that works as expected. - All I can say is "Brightwell Aquatics" makes some great products. I've used them for years. and trust my nano reef to them. Magnesium, Calcium, PH/Alk, pretty much anything I need to dose is from them. I have a 6 gallon nano reef tank and it can be a bit of a pain to dose, and keep parameters at the right levels. So far "Brightwell Aquatics" seems to work the best for smaller dosing without tanking or spiking. Review: Great product. - This works very well. My tank loves it. The coral is very happy and it didn’t have any side effects. Very easy to use and doesn’t cloud the water like others do. Great value. ## Features - HIGH-CONCENTRATION IONIC MAGNESIUM SOLUTION - Magnesion Liquid Reef Salt Water Conditioner is a high-concentrate solution for maintaining the optimal balance in aquarium reef tanks. Magnesium salt regulates aquarium calcium and carbonate concentrations to prevent excessive inorganic precipitation - REEF-BUILDING ESSENTIAL - Our aquarium water conditioner is a highly-concentrated ionic magnesium solution that plays a vital role in the formation of aragonite, the skeletal material of reef-building organisms like coral and clams - FREE FROM ORGANIC MATERIAL - This aquarium water conditioner contains no unwanted organic material such as EDTA, gluconate, or polygluconate, providing a pure formula for your aquarium's well-being. A powerful solution, it effectively boosts the health and vitality of aquatic ecosystems - DIRECTIONS – Before use, shake the supplement well. Administer 5 ml (1 capful) every other day, or as necessary, to sustain magnesium levels between 1,290 - 1,320 ppm in 20 gallons of aquarium water. When employed this way, 250 ml treats up to 1,000 gallons (3,785 L) - AMERICAN-MADE EXCELLENCE – Brightwell Aquatics is an industry-leading brand committed to providing innovative and scientifically backed aquatic care products. Made in the USA, we consistently deliver advanced superior quality solutions to elevate the vibrancy and health of your aquarium ## Technical Specifications | Specification | Value | |---------------|-------| | ASIN | B001DD2PN8 | | Allergen Information | Sulphites Free | | Best Sellers Rank | #12,751 in Pet Supplies ( See Top 100 in Pet Supplies ) #101 in Aquarium Water Treatments | | Brand | Brightwell Aquatics | | Brand Name | Brightwell Aquatics | | Customer Reviews | 4.6 out of 5 stars 435 Reviews | | Global Trade Identification Number | 00810086010370 | | Included Components | Magnesion | | Item Form | Liquid | | Item Type Name | Water Conditioner | | Item Weight | 0.25 Kilograms | | Liquid Volume | 8.45 Fluid Ounces | | Manufacturer | TopDawg Pet Supply | | Manufacturer Part Number | MAG250 | | Model Number | MAG250 | | Target Species | Fish | | UPC | 810086010370 | | Unit Count | 1 Count | ## Product Details - **Brand:** Brightwell Aquatics - **Item Form:** Liquid - **Item Weight:** 0.25 Kilograms - **Liquid Volume:** 8.45 Fluid Ounces - **Unit Count:** 1 Count ## Images ![Brightwell Aquatics Magnesion Ionic Magnesium for Reef Aquariums, 250 ml - Image 1](https://m.media-amazon.com/images/I/71bxwPciGWL.jpg) ## Customer Reviews ### ⭐⭐⭐⭐⭐ Nice product that works as expected. *by C***Y on January 5, 2026* All I can say is "Brightwell Aquatics" makes some great products. I've used them for years. and trust my nano reef to them. Magnesium, Calcium, PH/Alk, pretty much anything I need to dose is from them. I have a 6 gallon nano reef tank and it can be a bit of a pain to dose, and keep parameters at the right levels. So far "Brightwell Aquatics" seems to work the best for smaller dosing without tanking or spiking. ### ⭐⭐⭐⭐⭐ Great product. *by N***N on December 3, 2025* This works very well. My tank loves it. The coral is very happy and it didn’t have any side effects. Very easy to use and doesn’t cloud the water like others do. Great value. ### ⭐⭐⭐⭐⭐ Best magnesium we’ve used! *by K***S on September 16, 2025* Love this magnesium! Works great for our reef tank and worth the price!! It’s not too powerful that it throws our water parameters off, but gives us a boost when needed! Have purchased multiple times and will purchase again in the future! Exactly what we needed!! ## Frequently Bought Together - Brightwell Aquatics Magnesion Liquid Salt Water Conditioner - Concentrated Magnesium Supplement For Reef and Marine Aquariums, 8.45 fl oz - Salifert Magnesium (MG) Test Kit - Seachem Reef Calcium 250ml --- ## Why Shop on Desertcart? - 🛒 **Trusted by 1.3+ Million Shoppers** — Serving international shoppers since 2016 - 🌍 **Shop Globally** — Access 737+ million products across 21 categories - 💰 **No Hidden Fees** — All customs, duties, and taxes included in the price - 🔄 **15-Day Free Returns** — Hassle-free returns (30 days for PRO members) - 🔒 **Secure Payments** — Trusted payment options with buyer protection - ⭐ **TrustPilot Rated 4.5/5** — Based on 8,000+ happy customer reviews **Shop now:** [https://www.desertcart.hr/products/12258123-brightwell-aquatics-magnesion-ionic-magnesium-for-reef-aquariums-250-ml](https://www.desertcart.hr/products/12258123-brightwell-aquatics-magnesion-ionic-magnesium-for-reef-aquariums-250-ml) --- *Product available on Desertcart Croatia* *Store origin: HR* *Last updated: 2026-07-05*