Modern Reef - Proportional Consumption Reef Keeping System (RKS)

This comprehensive system comprises four canisters, each containing a precise blend of essential trace elements, organic and inorganic micronutrients, and amino acids, specifically formulated for the unique demands of closed reef aquarium environments. By harmoniously merging organic and inorganic components, this hybrid system offers the best of both worlds in a single product, empowering modern reef aquarists to create a thriving and vibrant reef ecosystem. The proprietary proportional consumption formula, developed and refined by Euro Corals, has been proven to foster exceptional coral growth and colouration, as demonstrated by the successful cultivation of remarkable coral specimens. Additionally, this innovative system includes ingredients used for the first time in the reef aquarium industry, making it even more effective and revolutionary. As the foundation of our proportional consumption reef-keeping methodology, the Modern Reef – Reef Keeping System (RKS) is complemented by Modern Reef Complete Reef Food and Polypop, ensuring a balanced and synchronized approach to reef care. Once the optimal maintenance dosage and ideal KH (carbonate hardness) level are established, this system provides a precisely calibrated supply of essential nutrients, trace elements, and amino acids proportionally linked to the consumption of KH and Ca (calcium), thereby promoting optimal reef health, colouration, and overall vitality.


  • Convenient 4-part dosing system ready to use.
  • With our expertly formulated system, you unlock the full potential of yellow and orange pigments, two of the most challenging colours to achieve in reef keeping.
  • Vibrant red, pink, blue, and purple pigments are brought to life.
  • Stimulate non-fluorescent chromoproteins to achieve more profound, more richly coloured pigmentation.
  • Optimized for blue-side spectrum light reef aquariums, our system excites and stimulates fluorescent proteins and reflective pigments for an unparalleled visual impact.
  • Experience accelerated growth rates when paired with Modern Reef Complete Reef Food and Polypop.
  • There is no need for constant magnesium and calcium testing – simply monitor KH levels for a hassle-free experience.
  • No additional products are required! Our system includes everything needed for coral colouration, polyp extension, and growth, aside from Modern Reef Complete Reef Food and Polypop.
  • Our proportional consumption reef-keeping system ensures precise dosing by calculation, eliminating the risk of overdose or unnecessary accumulation that can cause problems.
  • Our system, free of nitrates (NO3) and phosphates (PO4), promotes a healthy, thriving reef ecosystem.
  • It adapts seamlessly to any aquarium setup and nutrient export method, finding the optimal maintenance level for KH and the ideal KH level in harmony with calcium levels.
  • Enjoy improved water clarity as our system enhances the propagation of sponges and sea squirts.
  • SPS corals develop longer, more vibrant coloured tips, adding to the overall beauty of your reef aquarium.


Blue version: 10ml x100 liters will raise 1dKH
Black version 7.7x: 10ml x100 liters will raise 2dKH

Requirements and preparation

Modern Reef - RKS is a 4-equal-parts liquid solution, ready for use. Although manual dosing is possible, we strongly recommend utilizing a dosing pump, particularly for SPS-dominant reef aquariums, to ensure precise and consistent delivery. For optimal performance, we suggest employing a dosing pump with four heads, enabling simultaneous and accurate dosing of all four components. In the event that your dosing pump has only three heads, it is possible to combine one part of BASE KH1 with one part of BASE KH2 in a single canister or container. In this scenario, it is essential to multiply the combined BASE KH1 and BASE KH2 dosage by 2 to guarantee accurate and efficacious dosing.
For optimal dosing and a stable reef aquarium, consider the following tips:
  • To ensure optimal dosing pump performance, it is essential to maintain uniform tubing lengths from the canisters to the dosing pump heads and from the pumps to the aquarium. This consistency will facilitate constant calibration conditions.
  • Calibrate your dosing pumps according to the manufacturer's guidelines. Regularly verify the calibration every 6 months and recalibrate as necessary to maintain accuracy.
  • Configure the doser to dispense equal parts of each component, with a minimum 5-10 minute interval between each dosing pump cycle. A recommended sequence is to start with BASE KH1, followed by BASE CAL, then BASE KH2, and finally BASE MAG, with a 5-10 minute gap between each cycle.
  • To maximize the benefits of the Modern Reef RKS system, it is recommended to divide the daily dosage into multiple administrations throughout the day, as permitted by your dosing pump. This will ensure a consistent supply of essential trace elements to your reef aquarium, which can be rapidly consumed by your reef. Although some elements may become undetectable after a few hours, our system is designed to maintain a constant supply, preventing the "Greening Effect" caused by accumulation. By spreading the daily dosage across the day, you can optimize the unique proportional consumption formula of the Modern Reef RKS system.
  • Ozone, active carbon, and other absorbers should be avoided at all costs with Modern Reef RKS! These types of media can strip the water of essential ingredients and nutrients that are vital to the health and well-being of your reef aquarium. By using these media, you may inadvertently remove the very elements that the Modern Reef system is designed to provide, rendering your investment ineffective and wasting your money. The only exception to this rule is a UV filter, which is acceptable for use in conjunction with the Modern Reef system.

Dosing Guidelines and Recommendations

The following basic parameters have been extensively tested and validated by Euro Corals as optimal for maintaining a vibrant and healthy reef aquarium with Modern Reef:


390-440 mg/l


1280-1380 mg/l


7.2-8.5 dKH


>7 mg/l



Initiating the Modern Reef - Proportional Consumption RKS Method

To successfully implement our method, it is essential to first establish a stable foundation by maintaining calcium (Ca), magnesium (Mg), and carbonate hardness (KH) levels within the recommended ranges outlined above. If necessary, utilize Modern Reef KH+, Ca+, or Mg+ to achieve these parameters.

While nitrates (No3) and phosphates (Po4) levels can be adjusted to personal preference, we strongly recommend adhering to our suggested parameters when employing the Modern Reef - Proportional Consumption RKS method.

To begin, determine the maintenance dosage of KH (carbonate hardness) by dosing equal parts of each canister daily to maintain a KH level between 7.2-8.5 dKH. Subsequently, identify your ideal KH level for your specific reef aquarium system and setup, thereby completing the proportional consumption reef keeping system.

Determining the Maintenance Dosage of KH:

  1. Initiate dosing at 2.5-5 ml per 100 liters daily.
  2. Gradually adjust the dosage by 1-2 ml per 100 liters daily until you achieve a stable KH level between 7.2-8.5 dKH.
  3. Monitor KH levels daily using an accurate testing method, such as the Hanna Checker dKH, to ensure precise readings and adjustments.

Transitioning to Modern Reef from a Previous System:

If you're switching to Modern Reef from a previous system and know the concentration of your previous KH solution, follow these steps to determine your starting dosage:

  1. Determine how much your current KH solution raises KH levels per 10ml dose per 100 liters.
  2. Use the following formulas to calculate your starting dosage:
    • For Modern Reef Blue version: (10ml × KH increase per 10ml dose) / 1dKH
    • For Modern Reef Black version: (10ml × KH increase per 10ml dose) / 2dKH

Example Calculations

  • If 10ml of your current KH solution raises KH by 0.5dKH in 100 liters, and you're switching to Modern Reef Blue version:
    • (10ml × 0.5dKH) / 1dKH = 5ml per 100 liters
  • If 10ml of your current KH solution raises KH by 0.5dKH in 100 liters, and you're switching to Modern Reef Black version:
    • (10ml × 0.5dKH) / 2dKH = 2.5ml per 100 liters
Monitoring and Adjustments
After starting with the calculated dosage, monitor your KH levels daily and adjust the dosage as needed to maintain a stable KH level between 7.2-8.5 dKH. Use an accurate testing method, such as the Hanna Checker dKH, to ensure precise readings and adjustments.

Optimizing KH Levels for Your Reef Aquarium

Now that you've determined the maintenance dosage of KH, it's time to find the ideal KH level for your reef aquarium setup. To do this, focus on stabilizing calcium levels between 380-440ppm by dosing equal parts of calcium and alkalinity supplements. Then, test your KH levels to find the ideal range between 7.2-8.5dKH.

Tip: Once you've found the ideal KH level for your tank, you can reduce the frequency of calcium testing.

Scenario 1: Calcium Decrease

If you're dosing equal parts to maintain a KH level of 7.5, but your calcium levels are decreasing:

  • Increase your equal-parts dosage to raise KH to 7.7
  • Recheck calcium levels after one week
  • Repeat the process if necessary until calcium levels stabilize

Scenario 2: Calcium Increase

If you're dosing equal parts to maintain a KH level of 8, but your calcium levels are increasing:

  • Decrease your equal-part dosage to lower KH to 7.8
  • Recheck calcium levels after one week
  • Repeat the process if necessary until calcium levels stabilize

By following these guidelines, you'll be able to find the perfect balance of KH and calcium levels for your reef aquarium.

Actions when starting with RKS

Ca ↓
KH ↓

Increase RKS equal-parts dosage

Ca ↓
KH ↔

Increase your ideal KH level and dose Ca+ if needed

Ca ↓ |
KH ↑

Reduce your ideal KH level and dose Ca+ if needed


Continue with the same RKS dosage

KH ↓

Continue with the same RKS dosage and dose KH+

Ca ↑ 
KH ↓

Reduce your ideal KH level and dose KH+ if needed

Ca ↑ 

Reduce RKS equal-parts dosage

Comparing Value: Modern Reef RKS Set

When evaluating prices, it's crucial to consider the value you're getting for your money. Our Modern Reef RKS Set, which includes Complete Reef Food and Polypop, offers a comprehensive solution that provides a wide range of benefits for your reef aquarium, making it an unbeatable value.

All-in-One Convenience

Our Modern Reef RKS Set is a game-changer. With this comprehensive solution, you'll enjoy a powerful formula that covers an unparalleled range of benefits, including:

  • Coloration
  • Growth
  • Polyp extension
  • Vitality
  • Improved immune system
  • Vitamins
  • Amino acids
  • Solid food
  • Liquid food
  • Carbon dosing
  • Plus 3 proprietary ingredients used exclusively by Modern Reef

And, as part of our commitment to innovation, our formula, Reef-AquaForming, is already included in the set. This cutting-edge formula takes reef-keeping to the next level by strengthening your reef aquarium's immune system against cyanobacteria and dinoflagellates, creating a balanced and thriving ecosystem.

Streamlined Reef-Keeping

The best part? With our set, you won't need to purchase any additional products, making it a cost-effective solution in the long run. We've streamlined your reef-keeping experience, saving you time and money. Plus, you'll avoid the risk of over-dosing or mistakes that can be costly and harmful to your reef, especially for new reefers who may not be familiar with the complexities of reef-keeping.

Continuous Improvement

At Modern Reef, we treat our products like software. We're constantly monitoring and refining our formulas to ensure they're always up-to-date and effective. If we need to make updates, we do so seamlessly, without introducing new products or complexity. This means you can trust that our products will always deliver the best possible results for your reef aquarium.

The Reef Keeping System (RKS) requires Modern Reef Complete Reef Food and Polypop to complete the proportional consumption reef-keeping system. Please learn how to use them with RKS using the link below.

If you have any questions about our Modern Reef products or services, please don't hesitate to contact us.