The Coral Care Guide: Softies, LPS & SPS From First Frag

Walking into a local fish store and seeing a reef tank for the first time — corals swaying in the current, colors shifting under blue actinic light — is the moment most reef keepers trace their obsession back to. The path from that moment to a thriving home reef is more straightforward than the hobby's reputation suggests, but it does require understanding the three broad groups of corals you will encounter: soft corals, LPS (large polyp stony), and SPS (small polyp stony).

This guide walks through each group in the order most successful reef keepers follow — softies first, then LPS, then SPS — covering what each type needs to survive and what it takes to help them genuinely thrive. No shortcuts, no magic products, just the fundamentals that separate tanks that last from tanks that crash.

Understanding the Three Coral Groups

The soft coral, LPS, and SPS categories are practical hobby terms, not formal scientific classifications. They describe how corals are built, which drives almost everything about their care requirements.

Soft corals lack the rigid calcium carbonate skeleton that stony corals build. They are flexible, often leathery or rubbery in texture, and include mushrooms (Discosoma, Rhodactis, Ricordea), zoanthids, leather corals (Sarcophyton, Sinularia), green star polyps, xenia, and Kenya tree corals. Because they do not need to deposit heavy skeleton, they demand less calcium, alkalinity, and magnesium than stony corals — and they tolerate wider swings in those parameters.

LPS corals build a calcium carbonate skeleton but grow large, fleshy polyps over it. Think torch corals (Euphyllia glabrescens), hammer corals (Euphyllia ancora), frogspawn (Euphyllia divisa), brain corals (Favites, Goniastrea), candy cane corals (Caulastrea furcata), Duncan corals, and bubble corals. Those big polyps are built to capture food particles, which means LPS corals respond strongly to target feeding. Their skeletal growth creates a moderate demand for calcium and alkalinity supplementation.

SPS corals also build calcium carbonate skeletons, but their polyps are tiny — sometimes nearly invisible. Acropora, Montipora, Stylophora, Pocillopora, Seriatopora, and Porites are the genera most commonly kept. SPS corals grow rapidly under ideal conditions, consuming calcium and alkalinity at rates that demand consistent dosing or a calcium reactor. They also require strong lighting, stable parameters, and clean water with low nutrients — making them the final step in the difficulty progression.

The Progression: Why Order Matters

Starting with soft corals and working upward is not gatekeeping — it is risk management. A new tank goes through biological and chemical shifts that take months to stabilize. Diatom blooms, bacterial films, and nutrient spikes are normal during the first few months. Soft corals tolerate this turbulence. SPS corals placed in that same environment often bleach, recede, or die outright, costing real money and discouraging new hobbyists.

The proven timeline looks like this: set up the tank, cycle it, let it mature for three to four months, then add soft corals. Once those are growing and your maintenance routine is dialed in — stable salinity, consistent water changes, no ammonia or nitrite spikes — introduce LPS corals around the five- to seven-month mark. SPS corals should wait until the system has been stable for at least eight to twelve months and you are comfortable monitoring and dosing calcium, alkalinity, and magnesium.

This is not a rigid calendar. It is a stability benchmark. Some tanks mature faster than others. The indicator to watch is coralline algae — the purple and pink encrusting algae that grows on rock and glass. When coralline algae starts spreading, your water chemistry is in a range that supports calcification, which is exactly what stony corals need.

Lighting: The Single Biggest Variable

Corals contain symbiotic algae called zooxanthellae that photosynthesize and provide the majority of the coral's energy. Lighting intensity and spectrum directly control this process, which is why lighting is the single most important equipment decision in reef keeping.

Lighting intensity is measured in PAR (Photosynthetically Active Radiation), expressed in micromoles per square meter per second. Different coral groups need different PAR ranges:

Modern reef LEDs from manufacturers like Ecotech (Radion), AI (Hydra), Kessil, and Nicrew have largely replaced metal halide and T5 fluorescent lighting. LEDs offer adjustable intensity and spectrum, lower heat output, and programmable schedules that simulate sunrise, sunset, and cloud cover. The blue-heavy spectrum (around 420–460 nm) that makes corals fluoresce is also the range zooxanthellae use most efficiently, which is why reef tanks often look intensely blue.

When placing new corals, start them lower in the tank than their target position and move them upward gradually over two to four weeks. This prevents light shock — a common cause of coral bleaching in new additions.

Water Flow: Moving Water, Moving Nutrients

Flow delivers food particles to coral polyps, removes waste, and prevents detritus from settling on tissue — which causes tissue necrosis (RTN or STN in stony corals). Like lighting, different coral groups have different flow preferences.

Soft corals generally prefer low to moderate flow. Leathers and mushrooms can close up or detach in strong current. Zoanthids tolerate a wider range but do best in moderate, indirect flow. Xenia pulsing actually increases in gentle current.

LPS corals sit in the moderate range. Euphyllia species (torch, hammer, frogspawn) need enough flow to gently sway their tentacles without smashing them against the skeleton. Too much flow causes flesh recession; too little allows waste buildup that leads to bacterial infections.

SPS corals need strong, turbulent flow from multiple directions. Random, chaotic flow patterns — created by opposing powerheads or controllable wavemakers — mimic the natural reef environment where SPS species dominate exposed wave zones. A target turnover rate of 30 to 50 times the tank volume per hour (combining return pump and wavemakers) is a common SPS benchmark.

Water Chemistry: The Numbers That Matter

Reef keeping is ultimately water chemistry. Consistent, stable parameters matter more than hitting perfect target numbers. A tank sitting at 1.024 salinity consistently will grow better coral than a tank swinging between 1.023 and 1.026.

The core parameters every reef keeper monitors:

For soft coral-only tanks, standard water changes (10–15 percent weekly or biweekly) usually maintain adequate calcium and alkalinity without dosing. Once you add stony corals, you will need to supplement. The two most common approaches are two-part dosing (separate calcium and alkalinity solutions added daily) and calcium reactors (a chamber that dissolves aragonite media using CO2 to release calcium and carbonates). Two-part dosing is simpler for smaller tanks; calcium reactors become cost-effective when dosing demand exceeds about 50 mL per day of each part.

Feeding Corals: Light Is Not Enough

While zooxanthellae provide the bulk of energy for most corals, supplemental feeding measurably improves growth, coloration, and resilience — especially for LPS corals with large polyps designed to capture prey.

Soft corals absorb dissolved organic compounds and tiny phytoplankton directly from the water. Broadcasting a phytoplankton or coral food blend once or twice a week is generally sufficient. Reef Roids, Coral Frenzy, and Benereef are commonly used broadcast feeds.

LPS corals benefit most from target feeding — using a turkey baster, pipette, or feeding tube to deliver small pieces of frozen mysis shrimp, reef roids, or amino acid supplements directly onto polyps. Feeding after lights go out, when polyps are fully extended, produces the best response. One to three feeding sessions per week is typical.

SPS corals were long thought to be purely photosynthetic, but research and hobbyist experience have shown that they do capture bacterioplankton, phytoplankton, and dissolved amino acids. Amino acid supplements and fine coral foods can enhance SPS coloration — particularly the intense purples, greens, and blues that hobbyists prize.

Coral Dipping: Your First Line of Defense

Every coral entering your tank — whether from a store, an online vendor, or a fellow hobbyist — should be dipped in a coral pest treatment before placement. Coral dipping kills hitchhiker pests like flatworms, Acropora-eating flatworms (AEFW), nudibranch parasites, red bugs, and montipora-eating nudibranchs that can devastate a reef tank once established.

Common dip products include CoralRx, Bayer Advanced (diluted), Two Little Fishies Revive, and Brightwell Aquatics MediCoral. The process is simple: mix the dip solution with tank water in a separate container, submerge the coral for the recommended duration (typically five to fifteen minutes), shake it gently to dislodge pests, then rinse in clean saltwater before placing in the display tank.

Dipping is non-negotiable for SPS corals, where a single AEFW or montipora nudibranch introduction can strip an entire colony in weeks. For softies and LPS, dipping catches less destructive but still unwanted hitchhikers like aiptasia polyps, bristleworms, and predatory snails.

Fragging: Growing Your Collection for Free

Fragging — short for fragmenting — is the process of cutting a piece off a healthy coral colony to create a new independent coral. It is how reef keepers expand their collections without buying new specimens, trade with other hobbyists, and recover from losses by keeping backup frags in separate systems.

Soft corals are the easiest to frag. Mushrooms naturally split; leathers can be cut with scissors or a razor blade. Zoanthid mats can be separated by slicing through the connective tissue between polyps. Most soft coral frags heal within days.

LPS fragging requires cutting through the skeleton with a band saw, Dremel with a diamond blade, or coral bone cutters. The goal is clean cuts that avoid crushing tissue. Euphyllia species are fragged by separating individual heads at their natural branch points. Brain corals can be sectioned but have slower recovery times.

SPS fragging is straightforward — Acropora and Montipora branches snap cleanly at branch junctions. Frags are mounted to ceramic frag plugs or rubble rock using cyanoacrylate gel (super glue gel) or two-part epoxy, then placed in moderate flow and light to recover before being moved to their permanent position.

Common Beginner Mistakes

The mistakes that crash the most beginner reef tanks are predictable and preventable:

Adding corals too early. Patience during the maturation period pays enormous dividends. A tank that has been running stable for six months is a fundamentally different environment than one at six weeks, even if the water tests look identical.

Chasing numbers instead of stability. Adjusting parameters aggressively to hit a target number creates the swings that stress corals. Slow, gradual adjustments — no more than 0.5 dKH alkalinity change per day, for example — are safer than large corrections.

Skipping quarantine and dipping. Pest introductions are permanent. Once flatworms, AEFW, or nudibranch parasites establish in a display tank, eradication is extremely difficult. Dipping every coral and running a separate quarantine observation period is worth the effort.

Overstocking too fast. Adding many corals simultaneously can overwhelm the biological filtration and trigger nutrient spikes. Add one or two corals at a time, spaced at least a week apart, and monitor for parameter shifts.

Ignoring aggression. Corals compete for space. Many LPS corals extend sweeper tentacles at night that can sting and kill neighboring corals inches away. Spacing corals far enough apart to account for sweeper reach — and knowing which species are aggressive — prevents tissue loss and mysterious coral deaths.

Building a Sustainable Reef

The reef hobby has shifted meaningfully toward sustainability over the past decade. Captive-propagated and aquacultured corals are widely available, often hardier than wild-collected specimens because they have already adapted to aquarium conditions. Supporting vendors who propagate corals reduces pressure on wild reef systems and typically results in healthier, pest-free livestock.

Maricultured corals — grown on ocean farms rather than wild-harvested — represent a middle ground, offering the diversity of wild corals with reduced ecological impact. Many popular SPS species, including numerous Acropora varieties, are now available as mariculture frags.

The long-term goal for most reef keepers is a self-sustaining system where corals grow, frag naturally, and create new colonies without constant additions. Reaching that point requires months of patience, consistent maintenance, and a willingness to learn from the inevitable setbacks. The reward is a living ecosystem in your home that genuinely improves with age — something few other hobbies can claim.

Essential Equipment Checklist

Before adding your first coral, confirm your system includes these essentials: a quality reef LED light with adjustable spectrum and intensity, one or more wavemakers or powerheads providing adequate flow for your planned coral mix, a reliable refractometer for salinity readings, a comprehensive test kit covering at least calcium, alkalinity, magnesium, nitrate, and phosphate, and a supply of quality reef salt for water changes. An auto top-off (ATO) system is technically optional but practically indispensable — evaporation concentrates salinity daily, and an ATO maintains rock-steady levels with minimal effort. Add a reliable heater with a separate temperature controller as a safety backup, and you have the foundation that every successful reef is built on.