.aq-pd { font-family: Georgia, serif; color: #1a1a1a; max-width: 860px; margin: 0 auto; line-height: 1.7; } .aq-pd h2 { font-size: 1.45em; font-weight: 700; letter-spacing: -0.01em; border-left: 4px solid #006064; padding-left: 12px; margin: 2em 0 0.6em; } .aq-pd h3 { font-size: 1.05em; font-weight: 700; margin: 1.2em 0 0.4em; color: #006064; text-transform: uppercase; letter-spacing: 0.06em; font-family: Arial, sans-serif; } .aq-pd p { margin: 0.5em 0 1em; } .aq-callout { background: #003c3f; color: #fff; border-radius: 4px; padding: 16px 20px; margin: 1.6em 0; font-family: Arial, sans-serif; font-size: 0.93em; line-height: 1.6; } .aq-callout strong { color: #A7FFEB; } .aq-features { display: grid; grid-template-columns: repeat(auto-fill, minmax(240px, 1fr)); gap: 14px; margin: 1em 0 1.6em; } .aq-feature-card { background: #E0F7FA; border-radius: 4px; padding: 14px 16px; border-left: 3px solid #006064; font-family: Arial, sans-serif; font-size: 0.9em; } .aq-feature-card strong { display: block; margin-bottom: 3px; color: #1a1a1a; } .aq-feature-card span { color: #555; } .aq-compare { overflow-x: auto; margin: 1em 0 1.6em; } .aq-compare table { width: 100%; border-collapse: collapse; font-family: Arial, sans-serif; font-size: 0.88em; min-width: 520px; } .aq-compare th { background: #006064; color: #fff; padding: 9px 14px; text-align: center; font-weight: 700; letter-spacing: 0.05em; text-transform: uppercase; } .aq-compare th:first-child { background: #003c3f; text-align: left; } .aq-compare td { padding: 8px 14px; border-bottom: 1px solid #d0e8ea; text-align: center; } .aq-compare td:first-child { text-align: left; font-weight: 600; color: #444; background: #f5fbfc; } .aq-compare tr:nth-child(even) td:not(:first-child) { background: #f0fafb; } .aq-specs-table { width: 100%; border-collapse: collapse; margin-top: 1em; font-family: Arial, sans-serif; font-size: 0.93em; } .aq-specs-table th { background: #003c3f; color: #fff; text-align: left; padding: 9px 14px; font-weight: 600; letter-spacing: 0.04em; text-transform: uppercase; font-size: 0.82em; } .aq-specs-table td { padding: 8px 14px; border-bottom: 1px solid #e5e5e5; vertical-align: top; } .aq-specs-table tr:nth-child(even) td { background: #f7fcfd; } .aq-specs-table td:first-child { font-weight: 600; width: 45%; color: #444; } .aq-tab-radio { display: none; } .aq-tab-labels { display: flex; flex-wrap: wrap; gap: 8px; margin: 1.4em 0 0; } .aq-tab-label { display: inline-block; padding: 10px 22px; border: 2px solid #006064; background: #fff; color: #006064; font-weight: 700; font-family: Arial, sans-serif; font-size: 0.9em; cursor: pointer; border-radius: 3px; letter-spacing: 0.04em; transition: background 0.15s, color 0.15s; user-select: none; } .aq-tab-label:hover { background: #B2EBF2; } .aq-tab-panel { display: none; } #aq-tab-250:checked ~ .aq-tab-labels label[for="aq-tab-250"], #aq-tab-500:checked ~ .aq-tab-labels label[for="aq-tab-500"], #aq-tab-1000:checked ~ .aq-tab-labels label[for="aq-tab-1000"], #aq-tab-5000:checked ~ .aq-tab-labels label[for="aq-tab-5000"] { background: #006064; color: #fff; } #aq-tab-250:checked ~ .aq-panels #aq-panel-250, #aq-tab-500:checked ~ .aq-panels #aq-panel-500, #aq-tab-1000:checked ~ .aq-panels #aq-panel-1000, #aq-tab-5000:checked ~ .aq-panels #aq-panel-5000 { display: block; } .aq-note { font-family: Arial, sans-serif; font-size: 0.82em; color: #777; margin-top: -0.5em; font-style: italic; } Quantum Aragonite B is a concentrated liquid alkalinity supplement and the second part of Quantum's three part Aragonite reef dosing system. Alkalinity, also called carbonate hardness or KH, is what buffers your reef against pH swings and supplies the carbonate that corals lock into their skeletons. It is usually the fastest element a reef consumes. Aragonite B replaces it cleanly so your buffer stays rock steady. Pair it with Aragonite A (Calcium) and Aragonite C (Magnesium) for complete chemistry, and browse the rest of our reef additives and supplements. Alkalinity moves first. Of the big three, alkalinity is usually consumed fastest and swings hardest. Dose Aragonite B alongside A and C, test often, and a stable buffer will reward you with steady growth and better color. Why Alkalinity Matters Alkalinity is the carbonate side of coral growth and the buffer that holds your pH stable through the day and night cycle. When it drops, pH gets unstable and stony corals (SPS and LPS) can brown out or recede at the tips. Aragonite B lets you hold alkalinity in the ideal 8 to 9 dKH range. It works hand in hand with calcium (Aragonite A) and magnesium (Aragonite C), which is why all three are dosed together as a balanced set. Features Concentrated AlkalinityA strong carbonate buffer that goes a long way per dose. Reef Safe FormulaClean ingredients formulated specifically for marine and reef tanks. Part of a 3-Part SystemWorks hand in hand with Aragonite A (Calcium) and C (Magnesium). Stabilizes pHBuffers against the daily pH swings that stress corals. Made in AustraliaProduced by Quantum to a consistent, lab tested standard. Four SizesFrom a 250 ml nano bottle to a 5 L jug for large or multiple reefs. Choose Your Size Select a size in the tab section below for its full detail sheet. Spec 250 ml 500 ml 1 L 5 L Volume 250 ml 500 ml 1000 ml 5000 ml Best For Nano / pico reefs Small reefs Mid size reefs Large or multiple reefs Value per ml Good Better Great Best SKU AB250 AB500 AB1000 AB5000 Price $22.49 $30.49 $44.99 $139.99 Detailed Size Specifications Click a size below to view its full sheet. 250 ml · Nano 500 ml · Small 1 L · Mid 5 L · Large 250 ml · Nano & Pico Reefs The starter bottle. Ideal for nano and pico reefs, or for trying the Aragonite system before stepping up to a larger jug. Specification Value Volume 250 ml SKU AB250 Role Alkalinity (Part B) Best For Nano and pico reef tanks Price $22.49 500 ml · Small Reefs A practical everyday size for small reef systems with a light to moderate alkalinity demand. Specification Value Volume 500 ml SKU AB500 Role Alkalinity (Part B) Best For Small reef tanks Price $30.49 1 L · Mid Size Reefs The best balance of value and shelf life for most established reef tanks with steady coral growth. Specification Value Volume 1000 ml (1 L) SKU AB1000 Role Alkalinity (Part B) Best For Mid size reef tanks Price $44.99 5 L · Large or Multiple Reefs The bulk jug for large, heavily stocked SPS systems or hobbyists running several reef tanks. The lowest cost per ml. Specification Value Volume 5000 ml (5 L) SKU AB5000 Role Alkalinity (Part B) Best For Large or multiple reef tanks Price $139.99 Which Size Is Right for You? 250 ml — Nano and pico reefs, or a low commitment way to start the Aragonite system. 500 ml — Small reefs with a light to moderate alkalinity draw. 1 L — The sweet spot for most mid size reefs. Best mix of value and freshness. 5 L — Large SPS systems or multiple tanks where you want the lowest cost per ml. How to Dose Always test before you dose. Use a quality alkalinity (KH) test kit, then add Aragonite B to bring alkalinity into the 8 to 9 dKH range, raising it no more than about 1.4 dKH per day. Once you reach your target, dose a small daily amount to replace what your corals consume. Follow the dosing guide on the bottle and adjust to your own test results. Keep calcium, alkalinity, and magnesium in balance by dosing Aragonite A, B, and C together, and grab a reliable kit from our water testing collection. FAQ Why does alkalinity drop so fast?Growing corals pull carbonate out of the water constantly, and alkalinity is usually the first of the big three to fall. That is why frequent testing and steady dosing matter most here. What alkalinity level should I aim for?Most reef keepers hold 8 to 9 dKH. Test, then dose Aragonite B to reach and maintain that range. Avoid large swings. Do I need all three Aragonite products?Yes. Calcium, alkalinity, and magnesium are consumed together and keep each other in balance. Dosing only one will pull the others out of range over time. How is this different from Quantum Easy Z Alkalinity?Aragonite B is the single alkalinity component of the three part Aragonite system. Easy Z Alkalinity is part of a simpler two part approach. Both raise alkalinity; choose the system that fits how you like to dose.
