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Garlic,wheat and other foods absorbs selenium from the soil in which it grows. Selenium is an essential trace element for humans, animals, and reef life

Selenium (Se)

Chalcogens
Atomic Number: 34
Last Reviewed: 12/15/2024

Selenium is an essential micronutrient for many marine organisms, including fish and invertebrates. It is a component of selenoproteins, which are involved in antioxidant defense and thyroid hormone metabolism. However, maintaining appropriate selenium levels is critical, as both deficiency and excess can have adverse effects.

Natural Seawater Levels

Selenium concentrations in natural seawater are typically in the range of 0.04 to 0.12 µg/L. These levels can vary based on environmental factors and local biogeochemical processes.

Risks

Deficiency: Low selenium levels can impair antioxidant defenses and immune function in marine organisms, potentially leading to increased susceptibility to diseases.

Excess: Elevated selenium concentrations can be toxic, causing tissue damage and mortality in marine life. Toxicity thresholds are species-specific, but maintaining selenium within natural seawater levels is generally considered safe.


Relevancy

Biological Functions: Selenium is incorporated into selenoproteins that protect cells from oxidative damage and support immune function. In fish, adequate selenium levels are associated with improved growth and immune responses.

Microbial Interactions: Marine microorganisms play a significant role in the transformation of selenium, affecting its bioavailability and cycling within the ecosystem.

Ocean Values

Reference Name Low High Optimal Unit
Red Sea Ocean 1.0000 2.0000 1.5000 µg/L
Caribbean Ocean 0.7000 1.8000 1.1000 µg/L
Florida Ocean 1.0000 2.0000 1.4000 µg/L

Regional Variations

Selenium concentrations in seawater can vary based on local environmental factors, such as proximity to selenium⁻rich sediments or anthropogenic inputs.

Dosage Recommendations

Target Level: Maintain selenium concentrations within the natural seawater range of 0.04 to 0.12 µg/L.

Adjustment: Supplementation should only be undertaken if a deficiency is confirmed through reliable testing, with careful dosing to avoid exceeding safe levels.

Handling

Testing: Utilize advanced analytical methods for accurate measurement of selenium levels, acknowledging the limitations of standard aquarium test kits.

Intervention: Only consider supplementation if a deficiency is confirmed, and proceed with caution to avoid toxicity.


Reef.Tools recommends: Maintain Selenium (Se) concentrations between 0.0000 and 0.0030 µg/L.

References

  1. "Selenium in a Saltwater Aquarium and Its Importance." Reef Pedia. Reefpedia
  2. Ivanenko, N. V. "The Role of Microorganisms in Transformation of Selenium in Marine Waters." Russian Journal of Marine Biology, vol. 44, 2018, pp. 87–93. SpringerLink
  3. Maher, W. A., et al. "Modelling Selenium Behavior in Aquatic Systems: A Review of Status and Developments." Environmental Science and Pollution Research, vol. 31, 2024, pp. 395–408. SpringerLink
  4. Benayoun, G., et al. "Influence of Environmental Factors on Selenium Flux in Two Marine Species." Marine Biology, vol. 105, 1990, pp. 347–351. SpringerLink
  5. Ullah, K., et al. "An Overview of the Ongoing Insights in Selenium Research and Its Role in Fish Nutrition and Fish Health." Fish Physiology and Biochemistry, vol. 43, 2017, pp. 1689–1705. SpringerLink

Difficulty

Rating: Moderate

Maintaining appropriate selenium levels requires careful management due to its low concentration in seawater and the potential for toxicity if over-supplemented.

Categorization

Element Type: Non-metal

Role: Essential Trace Element

Not Usually Deficient

Regular water changes with quality salt mixes usually replenish selenium levels adequately.

Essential

Selenium is a critical component of selenoproteins involved in antioxidant defense and immune function in marine organisms.

Aliases

Se