Coral Types Comparison Guide | Characteristics and Difficulty Levels of Soft, LPS, and SPS Corals

Corals are the stars of a saltwater aquarium. Their vibrant colors and unique forms create the sensation of recreating an authentic ocean in your own home. However, the term "coral" encompasses an incredibly diverse range of species, each requiring different equipment and management levels.

Corals are broadly classified into three categories: "Soft Corals," "LPS (Large Polyp Stony Corals)," and "SPS (Small Polyp Stony Corals)." Understanding the differences between these three types is the first step to maintaining a successful coral aquarium long-term. This article will explain the characteristics, difficulty levels, and representative species of each, helping you choose what's right for your experience level and setup.

Soft Corals | Ideal Beginner-Friendly Starting Species

Soft corals are a collective term for "soft corals" that lack a hard, calcified skeleton. Most species contain microscopic skeletal elements called sclerites within their bodies instead of a rigid framework, characterized by their distinctive soft texture.

Care Characteristics

Soft corals have the widest tolerance for water quality variations among the three types, making them the easiest for beginners to manage. Many species can thrive without extremely high lighting, so a standard saltwater aquarium setup is sufficient to get started. Their relatively fast growth rate means you'll enjoy a lively tank early on—a very rewarding experience.

One concern to watch for is toxicity. Some species like Sea Anemones and Corallimorphs possess potent toxins. It's essential to confirm compatibility between fish and other corals before placing them in the same tank. Additionally, some species reproduce rapidly, potentially overgrowing other corals in the aquarium. Plan your layout with ample spacing.

Representative Species

• Button Polyps: Abundant color variations with high collectibility—a classic choice
• Toadstool Coral (Sea Toadstool): Popular for its distinctive frilly appearance; thrives with water flow
• Sea Anemone: Striking fluorescent colors that look fantastic in the tank, but be mindful of their toxicity
• Mushroom Coral: Gently sways like a mushroom with a soothing appearance
• Octopus Coral: Hardy and easy to raise—a beginner's gateway species

Care Difficulty: Low to Intermediate

LPS (Large Polyp Stony Coral) | Intermediate Species with Distinctive Forms and Feeding Joy

LPS, also called "Large Polyp Stony Corals," possess hard, calcified skeletons while developing large, fleshy polyps. The striking presence created by their unique skeletal shapes and broad, open polyps gives them exceptional aesthetic value as aquarium décor.

Care Characteristics

Compared to soft corals, LPS require somewhat more precise water quality management. If calcium (Ca) and carbonate hardness (KH) levels aren't maintained properly, skeletal formation may fail and the coral will weaken. However, it's less demanding than SPS—most species can be sustained with careful weekly water changes once or twice per week.

One of the great joys of LPS keeping is feeding. Watching them extend their tentacles to capture plankton and small food items is dramatic and captivating, almost plant-like in its movement. Supplementing with copepods, brine shrimp, or specialized coral foods promotes growth and enhances coloration.

Representative Species

• Euphyllia Coral: Beautiful flower-petal-like skeleton with abundant colors; perfect for LPS beginners
• Waving Hand Coral: Long tentacles gently sway in hypnotic fashion; be mindful of water flow direction
• Hammer Coral: Distinctive hammer-shaped polyps; hardy and easy to raise
• Ridged Coral: Neatly arranged polyps create beautiful patterns; becomes more impressive as it grows
• Bubble Coral: Adorable puffy, bubble-like polyps—a beloved favorite

Care Difficulty: Intermediate

SPS (Small Polyp Stony Coral) | Advanced Keepers' Dream, Ultimate Beauty

SPS, known as "Small Polyp Stony Corals," have extremely developed skeletons with polyps so minute they're barely visible to the naked eye. Acropora, the iconic SPS representative, is considered the "pinnacle" of the saltwater aquarium world. Their complex color gradients and delicate branching forms are truly natural art.

Care Characteristics

SPS keeping demands meticulous water quality management. The following water parameters must remain constantly stable:

• Ca (Calcium): 400–450 mg/L (essential for skeletal formation)
• KH (Carbonate Hardness): 8–9 dKH (involved in pH stability and skeletal formation)
• Mg (Magnesium): 1,250–1,350 mg/L (necessary to maintain Ca-KH balance)
• Nitrate and Phosphate: Keep as low as possible (close to 0 is ideal)

High-performance LED or metal halide lighting is mandatory, and strong water flow is essential. They're also sensitive to sudden changes in temperature and salinity (specific gravity). Equipment investment and daily management costs far exceed those of other types.

When you meet these challenging conditions, the fluorescent color gradients and luminous hues at branch tips reward you with an indescribable sense of accomplishment. Rare color morphs can command prices ranging from tens of thousands to hundreds of thousands of yen.

Representative Species

• Acropora (Stony Coral): The quintessential SPS; diverse forms from branching to tabletop
• Montipora Coral: Rounded shapes make it relatively hardy for SPS; beautiful coloration
• Pavona Coral: Plating and encrusting forms with striking colors

Care Difficulty: Advanced

Choosing by Your Level | The Stepwise Upgrade Approach

Coral keeping succeeds best when you progress gradually rather than jumping straight to difficult species.

Recommended Steps

1. Start with Soft Corals: Master water quality basics and experience the joy of watching corals thrive
2. Add LPS Once Your Tank Stabilizes: Discover the pleasure of feeding and learn the importance of refined water management
3. Challenge SPS After One Year of Experience: Invest in proper equipment, establish regular water-testing habits, and begin your advanced journey

Patient, steady experience is the key to maintaining a beautiful coral aquarium long-term. Since difficulty varies even within the same category, consulting with breeders or specialists before purchasing is highly valuable.

BreederDirect's Safe and Reliable System

On BreederDirect, you can purchase healthy fragments and parent corals directly from breeders without middlemen. Rare colors and breeder-specific specimens difficult to find through retail shops are readily available, with a lineup spanning from hardy beginner-friendly species to advanced rare varieties.

When purchasing, you can ask breeders directly: "What water conditions does this specimen thrive in?" and "What lighting do you use?" Getting this environmental transition information ensures minimal stress during acclimation.

Whether you're just starting your coral journey or aiming to level up an existing tank, be sure to explore BreederDirect's coral category. You'll find the perfect specimen for your aquarium.