Core Elements Bundle CAL/ALK/MAG
WB_CORE_ELEMENTS_PACK_CAL_ALK_MAG_1 · 500ml
The essential foundation for balanced reef chemistry. The Waterbox Core Elements Pack provides the three major components required for healthy coral growth and stable water chemistry—Calcium, Alkalinity, and Magnesium. These...
Or build it into a bundle — save up to 6% ↓What it is, and who it is for.
The essential foundation for balanced reef chemistry.
The Waterbox Core Elements Pack provides the three major components required for healthy coral growth and stable water chemistry—Calcium, Alkalinity, and Magnesium. These elements work together to support coral calcification, maintain proper pH, and promote vibrant, thriving reef systems.
Designed for use in all saltwater reef aquariums, this bundle simplifies dosing and helps ensure your water parameters remain stable and within optimal ranges. Maintaining proper levels of these core elements is critical for the long-term health, coloration, and structural growth of corals and other reef inhabitants.
Included in the Pack:
Calcium
Calcium is an essential building block for coral skeletons, invertebrates, and coralline algae. Without sufficient calcium, SPS and LPS corals cannot form their calcium carbonate structures, leading to poor growth and reduced vitality.
Recommended Levels: 420–460 ppm
Directions: 5 ml of Calcium raises calcium by 7.5 mg/L (ppm) per 100 L (25 gal).
Alkalinity
Alkalinity plays a vital role in maintaining pH stability and supporting coral skeleton formation. It prevents rapid pH swings and provides the carbonate ions needed for coral calcification.
Recommended Levels: 7.5–9.5 dKH
Directions: 5 ml of Alkalinity raises alkalinity by 0.125 dKH per 100 L (25 gal).
Magnesium
Magnesium helps maintain the balance between calcium and alkalinity by preventing precipitation and improving element absorption. Proper magnesium levels are key to stable reef chemistry and consistent coral growth.
Recommended Levels: 1200–1400 ppm
Directions: 5 ml of Magnesium raises magnesium by 3.75 mg/L (ppm) per 100 L (25 gal).
Together, these three elements form the chemical backbone of any successful reef aquarium—ensuring stability, strength, and vibrant coral development.
Build around the Core Elements Bundle CAL/ALK/MAG.
It's already in your system below. Add the flow, filtration and dosing around it and the discount starts working — tiers climb as the build grows, and the reef meter fills with it.
Pick the right one, not the biggest one
The honest line-up from supplements. Most buyers reading this page should buy the middle column.
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Core Elements Bundle CAL/ALK/MAG
Tropic Marin All-For-Reef SupplementAsked before checkout
The questions our support inbox actually gets.
Does it ship quickly?+
Orders placed before 2 PM ET on a business day leave the same day. Tracking is emailed the moment the label prints.
What if it's the wrong fit for my tank?+
Return it. 30 days, no restocking fee, refund to the original payment method. Better: tell us your tank first and we'll spec the system for free — half of all returns are sizing problems.
Who handles the warranty?+
We do. Everything carries the manufacturer's warranty and we run the claim for you — one email to us instead of a ticket queue.
How does the bundle discount work?+
Add items in the bundle builder: 2+ items saves 5%, 3+ saves 8%, 4+ saves 12%, and 5+ saves 15% off the whole system, applied at checkout.