Chromium is a trace element present in small quantities in the seawater of reefs all around the world.

Chromium is used to form enzymes for fat metabolisation in cells as such may have positive impacts on coral skeleton calcification, health and coloration.

Chromium gets depleted from the water in our tanks quickly. Naturally, Chromium in seawater varies strongly and is usually between 0.2-0.6 µg/l.

Too low chromium values lead to slow growth. Chromium plays an important role in the absorption and use of fatty acids in corals.

On a scale of 1-10 (1 low, 10 high) we classify the importance of chromium supplementation a 4 and suitable for experienced reefers only.

The use of our 2 part systems like Complete or pHplus will supplement Chromium helping to maintain adequate levels over time.

It is recommended to dose Chromium continuously (as needed) in as many small doses as possible. This will ensure Chromium is present and available in the water (despite precipitation and potentially being below the ICP limit of detection).

For ease of dosing and if you wish you can dose our elements via a dosing pump mixing them together in 2 solutions.

The following Reef Zlements elements can be mixed with chromium – barium, iron, cobalt, copper, manganese, nickel and zinc.

Please note that given the different products available in the market the above only applies to Reef Zlements trace elements and that we cannot guarantee the safety of the mix with other products.

To reach the desired level of 0.50 µg/l please dose 0.03 ml of Reef Zlements Chromium per day for 28 days.

Cobalt is a trace element present in a low concentration in oceans, varying between 0.002μg/L in north central Pacific Ocean and 0.39μg/L in Indian Ocean.

Cobalt is an integral part of vitamin B12 and plays a fundamental role in DNA; cell processes along being a nutrient for macro algae. It has been suggested that Cobalt might be a limiting factor of the bio-availability in the oceans and therefore an important trace element for the life of our animals.

Insufficient cobalt values reduce growth and colour formation.

Due to the extremely small amount needed in our aquariums, Cobalt is usually below the ICP detection limit. Nonetheless, despite potentially being present in undetectable levels the correction to reference levels will be ideal.

On a scale of 1-10 (1 low, 10 high) we classify the importance of cobalt supplementation a 4 and suitable for experienced reefers only.

The use of our 2 part systems like Complete or pHplus will supplement cobalt helping to maintain adequate levels over time.

It is recommended to dose Cobalt continuously (as needed) in as many small doses as possible. This will ensure Cobalt is present and available in the water (despite depletion and potentially being below the ICP limit of detection).

Please note that for reference one drop is approximately 0.02-0.05 ml. If your recommended dose is below 1 drop per day, feel free to dose every other day (or less).

For ease of dosing and if you wish you can dose our elements via a dosing pump mixing them together in 2 solutions.

The following Reef Zlements elements can be mixed with cobalt – barium, iron, chromium, copper, manganese, nickel and zinc.

Please note that given the different products available in the market the above only applies to Reef Zlements trace elements. We cannot guarantee the safety of the mix with other products.

To reach the desired level of 0.20 µg/l please dose 0.03 ml of Reef Zlements Cobalt per day for 12 days.

Copper is a trace element present in small quantities in the seawater of reefs all around the world.

Copper is an essential trace element that kept in small concentrations has positive impacts on coral skeleton calcification, health and colouration along being needed for multiple biological processes of corals and other organisms.

It is important to check Copper levels through ICP analysis and ensure adequate levels and stability by dosing a Copper supplement as needed.

Naturally, Copper in seawater varies but its concentration doesn’t go above 3 µg/l.

On a scale of 1-10 (1 low, 10 high) we classify the importance of copper supplementation a 5 and suitable for experienced reefers only.

The use of our 2 part systems like Complete or pHplus will supplement copper helping to maintain adequate levels over time.

It is recommended to dose copper continuously (as needed) in as many small doses as possible. This will ensure Copper is present and available in the water (despite precipitation and potentially being below the ICP limit of detection).

Please note that for reference one drop is approximately 0.02-0.05 ml. If your recommended dose is below 1 drop per day, feel free to dose every other day (or less).

For ease of dosing and if you wish you can dose our elements via a dosing pump mixing them together in 2 solutions.

The following Reef Zlements elements can be mixed with copper – barium, iron, chromium, cobalt, manganese, nickel and zinc.

Please note that given the different products available in the market the above only applies to Reef Zlements trace elements and that we cannot guarantee the safety of the mix with other products.

To reach the desired level of 0.20 µg/l please dose 0.04 ml of Reef Zlements Copper per day for 10 days.

Iron is present in reefs all around the world, being one of the most important elements for all animals and plants in our aquariums. Having a strong role in many different metabolic processes, including the transport of oxygen in the blood of animals.

Iron gets depleted (precipitates) from the water in our tanks very quickly.

Iron has been known to have a positive impact in aquariums where macro algae is present and to improve green colours.

It also plays an important role in the availability of nitrogen.

A deficiency of Iron can result in corals and biofilms (bacteria) not being able to process nitrogen compounds as well, if at all.

The reflection of this is that nutrients (NO3 and PO4) in the system increase substantially.

Often Iron is a limiting factor in the nitrogen cycle and carbon dosing (CarboPlus) will not perform as expected in reducing PO₄³⁻ and NO3- due to a lack of Iron.

A good Iron supplementation will improve the green and yellow colours in corals.

Iron not only precipitates quickly but, is also removed by filtration and consumed quickly, it is recommended that the dose shown below is performed weekly by splitting in to as many doses as possible (ideally dosed more than once a day).

On a scale of 1-10 (1 low, 10 high) we classify the importance of Iron supplementation a 7 and suitable for all levels of reefers.

The use of our 2 part systems like Complete or pHplus will supplement Iron helping to maintain adequate supplementation over time.

It is recommended to dose Iron continuously (as needed) in as many small doses as possible. This will ensure Iron is present and available in the water (despite the quick depletion and potentially being below the ICP limit of detection).

If you maintain macro algae please multiply your daily dose by 2x. However, if yellow corals do start to appear green, reduce the dose.

Please note that for reference one drop is approximately 0.02-0.05 ml. If your recommended dose is below 1 drop per day, feel free to dose every other day (or less).

For ease of dosing and if you wish you can dose our elements via a dosing pump mixing them together in 2 solutions.

The following Reef Zlements elements can be mixed with iron – barium, chromium, cobalt, copper, manganese, nickel and zinc.

Please note that given the different products available in the market the above only applies to Reef Zlements trace elements and that we cannot guarantee the safety of the mix with other products.

To reach the desired level of 0.40 µg/l please dose 0.03 ml of Reef Zlements Iron per day for 29 days.

Manganese is present in all reefs around the world, being an extremely important element for animals and plants in our aquariums.

Being a cofactor to many enzymes it has a strong role in the metabolic processes of almost all organisms, Manganese has been known to have a positive impact around the oxidative processes in organisms and is an essential element for corals having an impact in both growth and colouration (specially red).

Manganese in the aquarium precipitates quickly making it almost non-existent thus, can only be detected if the concentration is much higher than needed.

A lack of manganese is visible in dull tissue, reduced growth (or none at all), colourless growth tips and little to no polyp extension in Goniopora and Alveopora corals as well as light sensitivity in LPS.

Manganese also plays an important role in photosynthesis making it crucial for corals, algae and phytoplankton.

On a scale of 1-10 (1 low, 10 high) we classify the importance of manganese supplementation an 8 and suitable for all levels of reefers.

If GFO is used we recommend the additional supplementation of Manganese as GFO will absorb Mn.

The use of our 2 part systems like Complete/pHplus or our NO3/PO4 reduction supplement CarboPlus will supplement Manganese helping to maintain adequate levels over time.

It is recommended to dose Manganese daily and as in as many small doses as possible. This will ensure Manganese is present and available in the water (despite precipitation and potentially being below the ICP limit of detection).

If you maintain Goniopora corals, macro algae or a high coral bio-mass please multiply your daily dose by 2x.

Please note that for reference one drop is approximately 0.02-0.05 ml. If your recommended dose is below 1 drop per day, feel free to dose every other day (or less).

For ease of dosing and if you wish you can dose our elements via a dosing pump mixing them together in 2 solutions.

The following Reef Zlements elements can be mixed with manganese – barium, chromium, cobalt, copper, iron, nickel and zinc.

Please note that given the different products available in the market the above only applies to Reef Zlements trace elements and that we cannot guarantee the safety of the mix with other products.

To reach the desired level of 2.00 µg/l please dose 0.11 ml of Reef Zlements Manganese per day for 34 days.

Nickel is present in reefs all around the world and is an essential element for many marine creatures and bacteria as it promotes many enzymatic processes to occur.

With the ideal Nickel concentration, improvements in growth along with red and turquoise colours and contrast.

Nonetheless, Nickel gets depleted from the water in our tanks quickly.

Nickel has a growth-enhancing effect if ideal Nitrate levels are found in the water.

On a scale of 1-10 (1 low, 10 high) we classify the importance of nickel supplementation a 3 and suitable for experienced reefers only.

The use of our 2 part systems like Complete or pHplus will help to maintain adequate levels over time.

It is recommended to dose Nickel continuously (as needed) in as many small doses as possible. This will ensure Nickel is present and available in the water (despite precipitation and potentially being below the ICP limit of detection).

Please note that for reference one drop is approximately 0.02-0.05 ml. If your recommended dose is below 1 drop per day, feel free to dose every other day (or less).

For ease of dosing and if you wish you can dose our elements via a dosing pump mixing them together in 2 solutions.

The following Reef Zlements elements can be mixed with nickel – barium, chromium, cobalt, copper, iron, nickel and zinc.

Please note that given the different products available in the market the above only applies to Reef Zlements trace elements and that we cannot guarantee the safety of the mix with other products.

To reach the desired level of 2.50 µg/l please dose 0.15 ml of Reef Zlements Nickel per day for 32 days.

Selenium is a trace element present in small quantities in the seawater of reefs all around the world.

​Selenium is a very important trace element that kept in small concentrations has positive impacts on coral skeleton calcification, health and coloration along protecting the corals from oxidative compounds. To maximise its benefits Selenium should be used in conjunction with VitaPlus.

It is recommended to dose Selenium continuously (as needed) in as many small doses as possible. This will ensure Selenium is present and available in the water (despite precipitation and potentially being below the ICP limit of detection).

Please note that for reference one drop is approximately 0.02-0.05 ml. If your recommended dose is below 1 drop per day, feel free to dose every other day (or less).

On a scale of 1-10 (1 low, 10 high) we classify the importance of selenium supplementation a 5 and suitable for experienced reefers only.

For ease of dosing and if you wish you can dose our elements via a dosing pump mixing them together in 2 solutions.

The following Reef Zlements elements can be mixed with selenium – fluorine, iodine, lithium, molybdenum and vanadium.

Please note that given the different products available in the market the above only applies to Reef Zlements trace elements and that we cannot guarantee the safety of the mix with other products.

To reach the desired level of 0.20 µg/l please dose 0.03 ml of Reef Zlements Selenium per day for 12 days.

Zinc is a trace element present in reefs all around the world and is one of the most important elements for all animals and plants in our aquariums as it is involved in many metabolic and cellular processes.

Zinc concentrations in seawater normally vary between 0.6-5 µg/l, however, Zinc gets depleted from the water in our tanks very quickly.

Low Zinc concentrations will impair coral growth and render corals more sensitive to light and bleaching.

The nutrient cycle is also impacted and the bio-export of NO3 and PO4 is significantly reduced.

On a scale of 1-10 (1 low, 10 high) we classify the importance of zinc supplementation a 4 and suitable for experienced reefers.

The use of our 2 part systems like Complete or pHplus will help to maintain adequate levels over time.

It is recommended to dose Zinc continuously (as needed) in as many small doses as possible. This will ensure Zinc is present and available in the water (despite potentially being below the ICP limit of detection).

Please note that for reference one drop is approximately 0.02-0.05 ml. If your recommended dose is below 1 drop per day, feel free to dose every other day (or less).

For ease of dosing and if you wish you can dose our elements via a dosing pump mixing them together in 2 solutions.

The following Reef Zlements elements can be mixed with zinc – barium, chromium, cobalt, copper, iron, manganese and nickel.

Please note that given the different products available in the market the above only applies to Reef Zlements trace elements and that we cannot guarantee the safety of the mix with other products.

To reach the desired level of 5.00 µg/l please dose 0.37 ml of Reef Zlements Zinc per day for 18 days.

Alkalinity, also known as carbonate hardness, is a measure of the water’s ability to resist changes in pH caused by the addition of acids. It primarily consists of bicarbonate (HCO3-) and carbonate (CO32-) ions in the water. Alkalinity plays a crucial role in stabilizing pH levels and maintaining a suitable environment for aquatic organisms, primarily to corals.

Carbonate hardness pertains to the proportion of ions comprised of carbonates, substances that contain both carbon and oxygen. These carbonates serve as salts derived from carbonic acid, encompassing alkaline mineral ions existing as dissolved carbonates or hydrogen carbonates. For a substance to contribute to carbonate hardness, each carbonate and hydrogen carbonate ion must possess the ability to bind with a calcium or magnesium cation.

Alkalinity helps buffer the pH of the water, preventing rapid and harmful fluctuations. Reef organisms, especially corals and other calcifying organisms, are sensitive to alkalinity and pH changes. Maintaining stable pH levels is crucial for their health and growth.

Corals and other reef-building organisms utilize carbonate ions to build their skeletons and structures. Proper alkalinity levels ensure that these organisms have access to the necessary building blocks for growth and calcification.

Alkalinity interacts with calcium and magnesium ions in the water. If alkalinity levels are too high, it can lead to the precipitation of calcium carbonate (CaCO3), which can not only coat equipment, and other surfaces in the aquarium but, also lead to the overdosing of mineral mixes (e.g. 2, 3 or 4 part dosing systems) in order to maintain proper alkalinity/calcium levels. This can affect water and hinder coral health, create “concrete hard” clumps of rock, damage equipment amongst other issues.

Recommended alkalinity levels for a reef aquarium typically fall within the range of 7-8.5 dKH (degrees carbonate hardness) of alkalinity. It’s important to note that sudden and drastic changes in alkalinity can be harmful to the inhabitants of a reef aquarium. Therefore, any adjustments to alkalinity levels should be made gradually and with careful monitoring. Regular/daily testing of alkalinity is recommended to maintain a stable and healthy reef ecosystem.

With Alkalinity above 8.5-9dHK and a PO4 below 0.04ppm SPS corals start to show STN from the tips (aka burnt tips) and later from the base. Also if high alkalinity (above 8.5dKH) is maintained along high Iodine (i.e. above 75-80ug/l) SPS start to brown out.

To lower your alkalinity level we recommend stopping any alkalinity supplements (or stopping the calcium reactor), the use of a more natural levels salt can also be a possibility.

The acid binding capacity, also known as alkalinity or carbonate hardness, refers to the ability of the water in a reef aquarium to resist changes in pH when acids are added. It is a measure of the concentration of carbonate and bicarbonate ions (CO32- and HCO3-) in the water. These ions act as a buffer, helping to stabilize the pH of the water by neutralizing acids that may be introduced into the aquarium.

In a reef aquarium, maintaining a stable pH is crucial for the health and well-being of the inhabitants, particularly corals, which are sensitive to pH fluctuations. Alkalinity is closely linked to the carbonate equilibrium in the water, and it plays a vital role in various biological processes, including coral calcification and the overall stability of the aquatic environment.

Maintaining proper alkalinity levels ensures that the water can effectively buffer changes in pH, preventing rapid and potentially harmful fluctuations. It also supports the health and growth of corals and other reef organisms that depend on stable pH conditions for their physiological processes. Therefore, monitoring and adjusting alkalinity as needed is an essential aspect of reef aquarium maintenance.

For help please refer to the Alkalinity help section.

Calcium Carbonate Equivalent is a term used to express the amount of calcium carbonate (CaCO3) present in the aquarium water in terms of its potential to raise the pH.

In reef aquariums, calcium carbonate (CaCO3) is essential for the growth and calcification of corals and other calcifying organisms. Calcium and carbonate ions combine to form calcium carbonate, which serves as the building blocks for coral skeletons and structures.

While the term “Calcium Carbonate Equivalent” might not be commonly used in reef aquarium discussions, the underlying idea of understanding the actual calcium contribution of supplements is important for maintaining optimal water chemistry and supporting the health of coral and other calcifying organisms in the aquarium.

High Iodine values will lead to darkening of the corals and increased algae growth.

Nonetheless, a slow iodine level increase is quite benign and doesn’t seem to produce extreme issues. Nonetheless we recommend maintaining a level of Iodine between 60-80 µg/l.

An overdose of iodine will manifest itself quickly in SPS corals as it will quickly lead to a decrease in colouration and a complete browning of the corals.

Iodine overdoses are common and can be the result of dosing blindly, supplements containing it or some frozen foods.

To lower high Iodine concentrations from the aquarium use a high quality activated carbon like Reef Zlements activated carbon which you can find here and or perform 6x 20% water changes with a high quality salt.

Although corals will tolerate a high Molybdenum concentration well, this along with high nutrient levels will promote the growth of cyanobacteria. Nonetheless, Mo alone will not promote cyanobacteria.

We we therefore recommend the lowering of these levels by performing 6x 20% water changes with a high quality salt and the use of high quality activated carbon like our Z Reef Carbon which you can find here

Nitrate (NO3-) is a molecule that contains nitrogen and oxygen. In the context of a reef aquarium, nitrates are a byproduct of the nitrogen cycle, which is crucial for maintaining water quality and a healthy environment for the aquarium inhabitants, particularly in a reef aquarium.

Nitrates along with orthophosphate at ideal levels are considered important nutrients for corals, helping coral health and colouration. Idealy nitrates want to be kept below 25 in a 1:100 ratio to orthophosphate. With ideal levels and this ratio, the ideal NO3/PO4 conditions for coral health and algae control are achieved.

Nonetheless, if the nitrates are too high excessive bacteria (including cyanobacteria), undesireable algae can appear and corals tend to become darker so, it is important to maintain nitrates within the ideal range.

To keep nitrate levels in check, ensure that you use an adequately sized protein skimmer, employ efficient biological filtration, control feeding and waste accumulation in the tank. Additionally, you can add a refugium or algae reactor to the system.

To help both the biological filtration and macro algae we recommend the use of CarboPlus which you can find more information here

Orthophosphate (PO₄³⁻) is likely the most important nutrient in the reef aquaria when it comes to corals, however too much can lead to corals losing coral and becoming brown and to the reduction if coral growth.

It can also lead to algae and bacteria issues.

PO₄³⁻ swings can lead to STN/RTN so, it is important to carefully manage Phosphate levels.

To manage PO4 adequately, a conscious fish load and feeding should be observed, this will in turn help avoiding the deposits of organic matter containing undesired excess of nutrients.

We recommend the use of our new high efficient liquid Phosphate remover PhosFate or a good quality Granular Ferric Oxide (GFO) like RowaPhos.

Phosphorous is likely the most important nutrient in the reef aquaria when it comes to corals, however too much in the form of Orthophosphate can lead to corals losing colour, becoming brown and to the reduction of coral growth.

It can also lead to algae and bacterial issues.

Swings can lead to STN/RNT so, it is important to carefully manage Phosphorous/Phosphate levels.

To manage PO4 adequately, a conscious fish load and feeding should be observed, this will in turn help avoiding the deposits of organic matter containing undesired excess of nutrients.

We recommend the use of our new high efficient liquid Phosphate remover PhosFate or a good quality Granular Ferric Oxide (GFO) like RowaPhos.

Total Phosphate is the sum of all forms of phosphate present in a given sample. Phosphate (PO₄⁻) can exist in different chemical forms depending on factors such as pH, temperature, and the environment.

The three main forms of phosphate are:

• Orthophosphate (PO4³⁻) which is also measured with the Advanced ICP test, is also known as inorganic phosphate and is the most biologically available form of phosphate. It is directly used by corals, algae, bacteria and other organisms as a nutrient. Orthophosphate is the primary form of phosphate that aquarium hobbyists should focus on, as it has the most significant impact on the corals and the aquarium.
• Polyphosphates are composed of multiple phosphate molecules linked together. In water, they can break down into orthophosphate over time and become biologically available.
• Organic phosphates are phosphorus compounds bound to organic molecules, such as nucleic acids, phospholipids, and adenosine triphosphate (ATP). These compounds can also be contained in plants/algae, bacteria, detritus, etc. and are generally not readily available as a nutrient source for most aquatic organisms, as they need to be released into the water, broken down and converted into orthophosphate by biological processes before they can be utilized.

When measuring total phosphate via ICP testing, all these forms of phosphate are included in the analysis to get a comprehensive view of the total phosphorus content in a sample. This analysis is essential for understanding the nutrient dynamics and potential eutrophication (excessive nutrient enrichment leading to algal blooms) in aquatic environments, including in reef tanks.

For reef aquarium hobbyists, it’s often more critical to monitor and control orthophosphate levels since it is the primary form of phosphate that affects coral and algae growth in the tank.

High orthophosphate levels can lead to algae issues and negatively impact coral health, nonetheless reefers can likely infer the amount of detritus, plankton, bacteria and ultimately water quality level looking at the difference between the Total Phosphate and the Orthophosphate concentrations. The bigger the difference is the more likely is the presence of detritus, algae, bacteria, etc. in the water thus potentially reducing the water quality.

To resolve the above, reefers should use adequately sized skimmers, filter rollers like the Clarisea along with UV and Ozone systems which will help to remove these “detritus” from the water.

Following from the above a total phosphate concentration as close to the orthophosphate concentration as possible is likely a good indicator of a “clean water” free from detritus and other undesired bodies.

To manage PO4 adequately, a conscious fish load and feeding should be observed, this will in turn help avoiding the deposits of organic matter containing undesired excess of nutrients.

If the Orthophosphate is equally high, we recommend the use of our new highly efficient liquid Phosphate remover PhosFate or a good quality Granular Ferric Oxide (GFO) like RowaPhos.