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Ships within 48 hours · Estimated delivery Aug 6 - Aug 11
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Description
Seachem Laboratories Reef Advantage Calcium SupplementReef Advantage Calcium is a non caustic (pH 8. 3 8. 6) optimized blend of ionic calcium designed to restore and maintain calcium to levels found in natural seawater. Calcium and carbonates are essential to all coral growth. If either becomes deficient, coral growth will cease, followed by a rapid decline in coral health. To prevent this you must provide calcium (Reef Advantage Calcium) and carbonates (Reef Builder or Reef Carbonate). Reef Advantage
Reef Advantage Calcium is a non-caustic (pH 8.3-8.6) optimized blend of ionic calcium designed to restore and maintain calcium to levels found in natural seawater. Calcium and carbonates are essential to all coral growth. If either becomes deficient, coral growth will cease, followed by a rapid decline in coral health. To prevent this you must provide calcium (Reef Advantage Calcium) and carbonates (Reef Builder or Reef Carbonate). Reef Advantage Calcium also includes magnesium and strontium in amounts proportionate to typical utilization ratios (100:5:0.1, Ca:Mg:Sr). This allows one to maintain these two important elements while maintaining calcium. Unlike limewater (kalkwasser), Reef Advantage Calcium does not have a caustic pH and will not deplete magnesium. Used as directed, it will not deplete alkalinity. DO NOT OVERDOSE: Excess calcium may enhance the loss of carbonate alkalinity. Do not directly mix with any carbonate supplement. Best if calcium & carbonate additives are added on alternate days or at least 30 minutes apart. Guaranteed Analysis: Calcium (Ca) 34.7%; Magnesium (Mg) 1.73%; Strontium (Sr) 0.0346%Shipping Notes
- Free Standard Shipping on $100+ Orders to the USA.
- Except Preorder products are shipped in 48 hours.
- Delivery to the USA:
- Standard Shipping : 3-10 business days
- If time is of the essence, please consider selecting expedited delivery for faster service.
Exchange/Return Notes
- We offer a 30-day return/exchange service after receiving.
- Final sale items are not eligible for returns or exchanges.
- To process your return/exchange, please contact us at [email protected]
- Please click here for more details>>> Return & Exchange Policy
4.8 ★★★★★
Based on 23 reviews
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Product Reviews
★★★★★ 3
Cheap but stylish :) I still like
Cute, weird shoulders, cheap. Will tear fast, and earth. 1 thread and it’s overreeerrrrrr
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Reviewed in the United States on February 8, 2026
★★★★★ 5
Pleasant surprise
Size: Small, Color: Wine Red
Good quality. Love how the neck fits. The fabric is soft and comfortable. Size fits are accurate. I recommend this product. We purchased it twice in different colors. Worth the money!
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Reviewed in the United States on December 14, 2025
★★★★★ 5
Great quality nice fit
This turtle neck fit me just right I ordered a S I’m 5’11 207 lbs and it fit me perfect a nice slim fit. The neck wasn’t loose and the sleeves were long enough! The material was great nice and warm. It is a slim fit turtle neck and the quality of the fabric was great.
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Reviewed in the United States on February 20, 2026
★★★★★ 5
n/a
Size: Small, Color: Wine Red
great product I love it already and it actually fit and it was soooooooo comfortable
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Reviewed in the United States on May 7, 2026
★★★★★ 4
I wish it feels more cottom like
Size: Large, Color: A-black
The value is good, good product overall
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Reviewed in the United States on October 29, 2025