Water Chemistry Dosage Guidance from AskBRS: Understanding What, How Much, and When to Add!

Maintaining Water Quality in a Reef Aquarium: A Guide to Water Chemistry and Dosing

The health, growth, and overall stability of a reef aquarium ecosystem rely heavily on the management of water chemistry and dosing. By maintaining critical parameters such as salinity, pH, temperature, alkalinity, calcium, magnesium, and nutrient levels within specific ranges, you can mimic natural seawater conditions and support coral health.

Critical Water Parameters

Key elements for a thriving reef aquarium include salinity (~1.025 specific gravity), pH (8.1–8.4), temperature (76–82°F), alkalinity (8–12 dKH), calcium (400–450 ppm), and magnesium (1250–1350 ppm) [1]. These parameters provide the chemical environment that corals need to thrive.

Alkalinity and pH Stability

Alkalinity serves as a buffer against rapid pH changes, which can stress or damage corals. For stable alkalinity, frequent or large fluctuations should be avoided by dosing smaller daily amounts rather than large, infrequent doses [3].

Calcium and Magnesium

Calcium is a building block for coral skeletons, while magnesium is vital to maintain stability between calcium and alkalinity. Without adequate magnesium, calcium and alkalinity may precipitate out and become unavailable to corals [3].

Nutrient Control

Ammonia and nitrite levels must be kept at zero, and nitrates should remain low (<20 ppm) to prevent stress and algae overgrowth. Phosphate control is also important as high phosphate encourages undesirable algae [1].

Filtration and Biological Support

Live rock provides biological filtration by housing beneficial bacteria that break down waste. Protein skimmers remove organic compounds before they degrade and affect water quality [1].

Water Changes

Partial water changes (e.g., 10–20% weekly) replenish trace elements and maintain overall water chemistry balance. This helps replace depleted minerals and removes accumulated waste products [1][2][5]. The water used for changes should be prepped to match tank parameters closely to avoid shock [4].

Manual Dosing and Supplementation

For tanks with higher coral density or demanding species, manual dosing of calcium, alkalinity, and magnesium supplements helps maintain stable concentrations day-to-day. Trace elements can often be replenished via water changes or individual supplementation based on ICP test results [2][3].

Testing Frequency

Regular testing is essential to monitor parameters and adjust dosing accordingly: alkalinity and calcium twice a week, pH and salinity weekly, nitrates biweekly or more frequently depending on tank conditions [1][5].

Tools for Maintaining Water Chemistry

The AquaForest Component Bundle maintains all major, minor, and trace elements at the proper ratio found in natural seawater.
Dosing pumps are not mandatory but make the process easier by accurately delivering additives on a schedule.
"Tropic Marine All-For-Reef" is a one-part solution that maintains all major, minor, and trace elements in a reef tank.

Starting Out and Tank Demand

When first starting out, test for calcium and alkalinity daily, and after daily dosing amounts are dialed, adjust to weekly testing. Weekly water changes may not provide enough elements for corals in a reef aquarium, especially as more corals are added and they grow larger.

Three-Part Additive Systems

The BRS Pharma, AquaForest Component Bundle, and Tropic Marin Original Balling Set are three-part additive systems that maintain all major, minor, and trace elements. The BRS Pharma Hybrid Balling Method eliminates chloride buildup that comes with two-part dosing.

Understanding "Water Quality" and "Water Chemistry"

"Water quality" in an aquarium context refers to the suitability of water for supporting healthy aquatic life, including chemical, physical, and biological factors. "Water chemistry" directly refers to the molecular and/or chemical makeup of the water.

Calculating Doses

To calculate doses, test the aquarium's calcium and alkalinity levels daily for at least the first 5 days. ICP testing is a mail-in water testing service that tests for over 30 different elements in an aquarium's water. Magnesium is considered a major element but is not used up as fast as calcium and alkalinity, so it can typically be maintained once a week.

Dosing in a Reef Aquarium

"Dosing" is the action of using additives in a reef aquarium, typically to maintain water chemistry, add nutrition, add bacteria, or remedy certain problems. A "Two-Part (2 part) Solution" is an additive approach that contains two ionically balanced solutions, one for maintaining calcium and the other for maintaining alkalinity.

By following these guidelines and maintaining a balance in your reef aquarium's water chemistry, you can ensure a thriving environment for your corals and overall ecosystem stability.

Water Chemistry Dosage Guidance from AskBRS: Understanding What, How Much, and When to Add!