Coral care is an exciting and rewarding aspect of reef keeping, yet with all the information available, it can be difficult to separate fact from fiction. New hobbyists and experienced reef enthusiasts alike encounter a variety of myths that can lead to confusion—and potentially impact coral health. In this post, we’ll tackle some of the most common coral care myths and provide the accurate information you need to create a healthy and balanced reef tank.

Myth #1: "Corals Don’t Need Feeding; They Get Everything from Light"

While corals can gain nutrients through photosynthesis thanks to their symbiotic relationship with zooxanthellae (microscopic algae living within coral tissue), this doesn’t mean they don’t require additional feeding. Zooxanthellae indeed supply corals with sugars through photosynthesis, but corals also benefit from consuming other nutrients, like plankton, invertebrate larvae, and dissolved organic matter in the water.

Adding appropriate coral foods to your tank provides valuable amino acids and other nutrients that photosynthesis alone may not fully supply. This is especially important for non-photosynthetic corals, which rely entirely on external feeding.

• Fact: Feeding corals with supplemental nutrients enhances their growth, coloration, and overall health. Many aquarists find that their corals grow faster and display more vibrant colors when fed regularly with specialized coral foods.

Myth #2: "High Lighting Is Always Better for Coral Health"

Another common coral misconception is that high lighting is essential for all corals. While some corals, particularly SPS (Small Polyp Stony) corals, do require intense lighting, others, such as LPS (Large Polyp Stony) and many soft corals, thrive in moderate or even low lighting. Overly bright lighting can stress certain corals, leading to bleaching or even death.

Each coral species has specific lighting needs based on its natural habitat. To create the ideal environment, research each species’ requirements and adjust the light intensity accordingly.

• Fact: Not all corals need high-intensity lighting. Adjust your lighting levels based on the specific needs of your coral species to avoid overstressing them.

Myth #3: "All Corals Need Pristine, Ultra-Clean Water"

Many people believe that corals require water that’s almost devoid of nutrients, but this isn't entirely accurate. In the wild, coral reefs exist in nutrient-rich environments, and many corals actually benefit from trace levels of nitrates and phosphates. While keeping water parameters stable is essential, striving for "zero" nutrient levels can lead to poor coral health, as corals require certain nutrients to thrive.

The key is to maintain balanced nutrient levels without letting them reach excessive levels. Slightly elevated nitrate and phosphate levels can enhance coral growth, especially for corals that benefit from organic matter in the water.

• Fact: A well-balanced nutrient level, not ultra-clean water, is ideal for coral health. Maintaining low but stable levels of nitrates and phosphates can improve coral growth and coloration.

Myth #4: "All Corals Require the Same Water Flow"

The idea that all corals need the same type of water flow is misleading, as corals have varied preferences depending on their species. Some, like SPS corals, prefer strong, turbulent water flow that mimics their natural environment on wave-exposed reefs. Others, such as certain LPS and soft corals, prefer gentler, steady currents that allow them to extend their polyps without being overwhelmed.

Providing the correct water flow is essential for coral health, as it influences nutrient delivery, waste removal, and oxygenation. Using adjustable powerheads allows you to create zones with different flow rates, catering to the needs of various coral species within the same tank.

• Fact: Corals have different flow requirements depending on their species. Tailoring water flow to match the needs of each coral type will help them thrive.

Myth #5: "Corals Only Survive in Large Tanks"

While large tanks certainly provide more stable conditions, especially for beginners, corals can thrive in smaller tanks if water parameters are consistently monitored. Nano tanks or small aquariums are increasingly popular for coral enthusiasts with limited space. Many species, particularly soft corals and certain LPS corals, can adapt well to nano tank environments.

Small tanks require diligent maintenance, as fluctuations in water parameters are more pronounced. However, with careful monitoring and a proper maintenance routine, hobbyists can keep vibrant and healthy corals in smaller setups.

• Fact: Corals can thrive in small tanks as long as water parameters are monitored and maintained consistently. Small tanks require more frequent maintenance but can house many types of corals successfully.

Myth #6: "Corals Can’t Be Placed Too Close Together"

Corals may appear peaceful, but many species exhibit aggressive behaviors, particularly when competing for space. Some corals have “sweeper” tentacles with stinging cells that they use to damage neighboring corals, while others may release chemicals that inhibit the growth of nearby species. Placing corals too close together can lead to stinging, chemical warfare, or shading, where taller corals block light from reaching those below.

Spacing corals appropriately is essential for preventing aggression and ensuring they receive adequate light and flow. Observing each species’ behavior and growth pattern will help in creating a layout that minimizes competition.

• Fact: Coral aggression is real; some species may sting or compete with others if placed too closely. Arrange corals with sufficient space to avoid competition and aggression.

Myth #7: "Adding Corals Is Easy—Just Place Them in the Tank"

One of the most pervasive myths in reef keeping is that corals can simply be placed in the tank without acclimation. In reality, corals are sensitive to changes in water chemistry, temperature, and lighting. Failing to acclimate new corals can lead to stress, bleaching, or even death. Coral acclimation usually involves a drip method to gradually match the tank's water parameters, reducing the shock that can result from sudden changes.

Quarantining corals before introducing them to the main tank is also highly recommended to prevent the spread of pests or diseases.

• Fact: Proper acclimation is essential for coral health. Gradual acclimation to your tank’s conditions minimizes stress and improves the likelihood of a successful introduction.

Building a Better Reef with Accurate Coral Care Knowledge

Understanding the reef tank facts and debunking these common coral misconceptions can make a significant difference in your success as a reef hobbyist. By relying on accurate information, you can create an environment where corals not only survive but thrive. Proper feeding, lighting, water flow, and placement can each contribute to a vibrant, flourishing reef tank.

As the popularity of reef keeping grows, so does the need to share correct information and practices. Embracing a fact-based approach to coral care ensures that both beginners and experienced aquarists can enjoy the beauty and rewards of a healthy reef. Avoid these myths, and you’ll be on your way to cultivating a stunning and sustainable underwater world.