New Arrivals/Restock

Seachem Reef Advantage Calcium, 8.8 oz

flash sale iconLimited Time Sale
Until the end
07
17
49

$8.39 cheaper than the new price!!

Free shipping for purchases over $99 ( Details )
Free cash-on-delivery fees for purchases over $99
Please note that the sales price and tax displayed may differ between online and in-store. Also, the product may be out of stock in-store.
New  $13.99
quantity

Product details

Management number 244422451 Release Date 2026/07/20 List Price $5.60 Model Number 244422451
Category

Seachem Reef Advantage Calcium is a non-caustic (pH 8.3-8.6) optimized blend of ionic calcium designed to restore and maintain calcium levels to those found in natural seawater. Note that if either calcium or carbonates become deficient, coral growth will cease, followed by a rapid decline in coral health.

  • Raises calcium to natural seawater levels
  • Capable of raising 20 gallons of water by 25 ppm of calcium with only 1 teaspoon
  • Non-caustic and pH balanced (pH 8.3-8.6)
  • Maintains magnesium and strontium, will not deplete alkalinity

In addition to calcium, Reef Advantage provides magnesium and strontium in amounts proportionate to typical utilization ratios (100:5:0.1, Ca:Mg:Sr), helping to maintain three critical elements at once. Unlike limewater (kalkwasser), Reef Advantage Calcium does not have a caustic pH and will not deplete magnesium. When used as directed, it will not deplete alkalinity.

Directions:
BEGINNER: Use 5 g (1 level teaspoon) per 150 L (40 US gallons) twice a week. For precise dosing, use the Seachem Digital Spoon Scale. Dissolve in at least 250 ml (1 cup) of freshwater. Check calcium every 2 weeks and adjust amount or frequency accordingly.

ADVANCED: Check calcium level, then follow addition regimen above until calcium is adjusted to 380–420 mg/L. Each 5 g/150 L will raise calcium by about 12 mg/L. Quantity or frequency can be adjusted, but do not exceed 10 g/150 L per day. Thereafter, use as required to maintain calcium.

EXPERT: After determining the calcium consumption rate, set up a continuous drip system. Use the following formula to determine how much to add to your top-off water: m=vc/400 (m=grams to add to top off water, v=volume of tank in liters, c=amount to raise calcium in mg/L). [For reference: 1 gallon=3.8 liters, 5 g=1 teaspoon].

DO NOT OVERDOSE: Excess calcium may enhance the loss of carbonate alkalinity. Do not directly mix with any carbonate supplement. Best if calcium and carbonate additives are added on alternate days or at least 30 minutes apart.

Ingredients: Calcium Chloride, Magnesium Chloride, Strontium Chloride.

Guaranteed Analysis:
Calcium (Ca) (min) - 335 mg; (max) - 347 mg
Magnesium (Mg) (min) - 17 mg
Strontium (Sr) (min) - 0.34 mg

Oops, this item is out of stock! But don’t worry—our Special Deals section is packed with amazing finds at even better prices. Explore now and score exclusive discounts you won’t want to miss!

Correction of product information

If you notice any omissions or errors in the product information on this page, please use the correction request form below.

Correction Request Form

Product Review

You must be logged in to post a review