Coral Care Guide

A quick-reference guide to keeping healthy corals, broken down by category. We’ll keep adding to this over time as new topics come up. Start here:

• Cycling a New Tank
• Water Chemistry Basics
• UV Sterilization
• Protein Skimmers
• Auto Top-Off (ATO) Systems
• How to Dip Corals (and Why You Should Never Skip It)
• Feeding a Reef Tank: Fish, Corals, and Nutrient Management
• Nitrate & Phosphate: Target Ranges by Tank Type (and Why Stability Beats Zero)
• How Often to Test Your Reef Tank (and Why It’s Non-Negotiable)
• Aquacultured vs. Wild Coral: What You’re Actually Paying For
• Acclimating & Quarantining Marine Fish: Ich, Black Ich, Velvet & More
• How Many Fish? Stocking Guide from Nano to Large Tanks
• Water Changes: How Much, How Often, and Why Twice a Month Beats Once
• Algae ID Guide: Hair Algae, Bubble Algae, Diatoms, Cyano & Dinoflagellates
• Clean-Up Crew 101: Snails, Hermits, Starfish & Algae-Eating Fish
• Reactors Demystified: Biopellet, GFO & Carbon (and When You Actually Need One)
• Live Rock vs. Dry Rock: Pros, Cons, and the Hybrid Method
• Reef Dosing Explained: 2-Part, 4-Part, Kalkwasser & the Moonshiner’s Method
• Copepods 101: Tigger Pods, Tisbe, Apocyclops & the Phytoplankton Connection
• Common Reef Tank Pests: Aiptasia, Asterina, Vermetid Snails & Hydroids
• Spot Feeding Corals: How, When, and Why It Matters (Plus Amino Acids)
• Reef Tanks as Therapy: What the Science Says About Aquariums, Blood Pressure, and Mental Health

• Soft Corals
• LPS Corals
• SPS Corals
• Mushroom Corals
• Water Flow
• Lighting

---

Cycling a New Tank

Before any coral or fish goes in, your tank needs a colony of bacteria that converts waste into something safe. Skipping or rushing this step is the most common reason new tanks crash.

Substrate: Sand beds give bacteria more surface area and suit beginners; bare bottom is easier to keep spotless and popular for SPS/frag setups.

Live Rock & Filter Media: Live or cured dry rock is your main biological filter; adding a biological media block (like Marine Pure) dramatically increases surface area for bacteria in a small footprint.

The Nitrogen Cycle: Ammonia converts to nitrite, then nitrite to nitrate. Once ammonia and nitrite both read zero for 2–3 weeks straight, the tank has cycled.

Speed It Up: Bottled bacterial starters (MicroBacter7, Bio-Spira, BioPronto) can cut weeks off the process; turn off UV and skimmers while dosing.

Ready for Livestock: Once ammonia and nitrite read zero and your clean-up crew is established, add livestock gradually rather than all at once.

---

Water Chemistry Basics

Once a tank is cycled, water chemistry is what keeps it stable long term. None of these numbers matter in isolation — consistency matters more than any single reading.

Salinity: Maintain 1.024–1.026 specific gravity (about 35 ppt) using a refractometer, not a hydrometer; pair with an ATO to keep it from drifting as water evaporates.

Alkalinity & Calcium: Target 7–12 dKH alkalinity and 380–450 ppm calcium — the two building blocks corals use to grow their skeletons, usually dosed and tested together.

Magnesium: Keep it around 1,200–1,400 ppm; low magnesium is often the hidden reason calcium and alkalinity won’t hold steady.

Nitrate & Phosphate: Target low but detectable levels (roughly 3–15 ppm nitrate, 0.03–0.10 ppm phosphate) rather than zero — true zero starves corals.

Testing: Test alkalinity, calcium, and magnesium once or twice weekly, nitrate/phosphate weekly, and salinity with every water change.

---

UV Sterilization

A UV sterilizer is one of the most misunderstood pieces of equipment in the hobby — not a cure-all, but genuinely useful for water clarity and pathogen control when sized and run correctly.

What It Does: Water passes through a chamber with a UV-C bulb that disrupts the DNA of free-floating algae, bacteria, and parasites so they can’t reproduce.

What It Can’t Do: It only affects organisms suspended in the water column — it won’t touch algae or bacteria already established on rock or glass, and it’s not a substitute for quarantining new fish.

Sizing: Turn over your total tank volume through the unit about 3 to 4.5 times per hour; slower flow means more contact time and better parasite control.

Maintenance: Replace bulbs every 9–12 months even though they’ll still glow after they stop putting out effective UV-C, and keep the quartz sleeve clean.

---

Protein Skimmers

A protein skimmer is one of the few pieces of equipment we consider genuinely essential — it pulls organic waste out of the water before it ever breaks down into ammonia and nitrate.

How It Works: Foam fractionation mixes air with tank water, and dissolved organics cling to the resulting bubbles, which rise and spill waste into a collection cup.

Sizing: Oversize rather than undersize — aim for a skimmer rated around 1.5x your tank volume for a moderately stocked tank, and 2x or more for a heavily stocked one.

Break-In: A new skimmer needs 5–7 days (sometimes up to 2–4 weeks) with the outlet fully open before it skims well — don’t judge performance until then.

Maintenance: Empty and rinse the collection cup at least twice a week, and periodically clean the pump and neck of salt creep buildup.

---

Auto Top-Off (ATO) Systems

Evaporation happens every day in every tank. An ATO automatically replaces that lost freshwater before it becomes a salinity problem — one of the least exciting purchases you’ll make, and one of the most important.

How It Works: A water level sensor pairs with a small pump and a reservoir of RO/DI water, topping off automatically whenever evaporation drops the level.

Why It Matters: Only H2O evaporates, so unreplaced water loss makes salinity climb day after day; an ATO holds it essentially constant and protects your return pump from running dry.

Reservoir Sizing: A 5-gallon reservoir typically buffers a tank up to about 75 gallons for several days; frequent travelers should size up to 10–15+ gallons.

Our Pick: The Tunze Osmolator is our top recommendation, thanks to its optical sensor and a backup float switch that shuts off the pump and alarms if the primary sensor fails. Read the full reef-tank ATO setup and safety guide for sensor placement, reservoir planning and maintenance.

---

How to Dip Corals (and Why You Should Never Skip It)

Every coral has spent time outside a controlled reef system before it reaches your tank, and one that looks perfectly healthy can still carry pests or bacteria that won’t show up for weeks. Dip every new coral, no exceptions.

Iodine (Lugol’s): A strong disinfectant, best for bacterial infections, brown jelly disease, and fresh frag cuts — dilute strictly to label.

Hydrogen Peroxide: Great for stripping algae and biofilm off zoas; SPS and LPS are more sensitive, so use a weaker dilution.

Revive (Two Little Fishies): A gentle, all-around everyday dip for every new arrival that knocks loose pods, flatworms, and debris.

Freshwater Dips: Powerful against flatworms and nudibranchs via osmotic shock, but risky — keep to 15–30 seconds and watch closely.

Always Rinse: Transfer the coral to a separate container of clean, tank-temperature saltwater for about a minute before it goes anywhere near your display.

---

Feeding a Reef Tank: Fish, Corals, and Nutrient Management

Feeding is the biggest lever you have over both coral growth and water quality. A tank fed well grows fast and stays stable; a tank fed carelessly fights algae and swinging nutrients no matter how good the equipment is.

Two Different Mouths: Fish need protein-rich meaty foods (and greens for herbivores); corals filter-feed on particles too small to see — feed each intentionally rather than treating it as one routine.

Coral Foods: Reef-Roids and BeneReef are popular powdered foods — target-feed directly onto polyps with a syringe rather than broadcasting, since it’s easy to overdose and drive up nitrate and phosphate.

Nori for Grazers: Tangs, angelfish, and other herbivores need plain, unseasoned dried seaweed clipped to the glass as a staple, not an occasional treat.

Avoid Overfeeding: Feed only what fish finish in a minute or two, and remember that uneaten food and waste both break down into nitrate and phosphate.

Nutrient Export: Pair careful feeding with real export — a skimmer, refugium, GFO, or carbon dosing — rather than relying on water changes alone.

---

Nitrate & Phosphate: Target Ranges by Tank Type (and Why Stability Beats Zero)

Nitrate and phosphate aren’t waste to be eliminated — they’re nutrients every coral needs. The goal is holding both in a range that suits what you’re keeping, and holding that range steady.

SPS-Dominant: Nitrate 2–10 ppm, phosphate 0.01–0.03 ppm — SPS wants it lean.

Mixed Reef: Nitrate 5–15 ppm, phosphate 0.03–0.10 ppm — a compromise range that keeps everything fed.

LPS & Soft Coral: Nitrate 10–20 ppm, phosphate 0.05–0.15 ppm — these corals tolerate, and often benefit from, dirtier water.

FOWLR: Nitrate under 20 ppm, phosphate under 0.10 ppm as a general ceiling, with the main concern being algae control.

Stability Over Perfection: A tank holding a steady 10 ppm nitrate will almost always outperform one bouncing between 2 and 20 ppm — track the trend, not any single reading. Compare the full nitrate and phosphate target ranges by tank type before changing your nutrient-export routine.

---

How Often to Test Your Reef Tank (and Why It’s Non-Negotiable)

Corals and fish can’t tell you when something’s drifting out of range. Testing is your only real window into what’s happening in the water, and how often you test matters as much as what you test for.

Alkalinity: 2–3 times per week in coral-heavy and SPS-dominant tanks — it’s the most volatile major parameter.

Calcium & Magnesium: Weekly to biweekly for calcium, every 1–2 weeks for magnesium.

Nitrate & Phosphate: Weekly, or more often while dialing in a new tank or troubleshooting algae.

New vs. Established Tanks: Newer tanks need more frequent testing across the board; “established” doesn’t mean you stop.

Keep a Log: A single reading tells you little — a log turns individual numbers into a trend you can actually act on.

---

Aquacultured vs. Wild Coral: What You’re Actually Paying For

Every coral for sale got there one of two ways — propagated in a controlled system, or collected straight off a natural reef. Both are legal, but the path affects hardiness, price, and the reef it came from.

What Aquacultured Means: Propagated from a fragment in a monitored farm or hobbyist tank over months to years before it’s ever sold.

What Wild Means: Collected directly from a natural reef under export permit, going through far fewer hands and far less monitored care.

Why Aquacultured Costs More: You’re paying for grow-out time, hand-selection for color and hardiness, and a much lower-risk animal.

The Risk of Wild Coral: Wild colonies are meaningfully more likely to carry pests and disease, and are more prone to RTN/STN and acclimation trouble.

Our Approach: Most of our coral is aquacultured or conditioned in our Key West systems. Product listings identify the source when known.

---

Acclimating & Quarantining Marine Fish: Ich, Black Ich, Velvet & More

More fish are lost in the first few weeks after purchase than at any other point — usually from poor acclimation or an uncaught parasite. Getting this right is the difference between a fish settling in and a tank-wide outbreak.

Drip Acclimation: Float the bag 15 minutes to match temperature, then drip acclimate in a separate bucket over 30–60+ minutes — never pour bag water into your tank.

Quarantine Is Non-Negotiable: Quarantine every new fish for 4 weeks minimum; most effective medications (like copper) aren’t reef safe.

Marine Ich: White salt-like spots; treat with copper, hyposalinity, or the tank transfer method — all require a dedicated quarantine tank.

Marine Velvet: The most dangerous disease on this list, fast-moving; treat immediately with copper at 0.15–0.20 mg/L, tested daily.

Black Ich & Intestinal Parasites: Praziquantel is the go-to treatment for black ich (about a week) and, combined with metronidazole, for internal parasites via medicated food.

---

How Many Fish? Stocking Guide from Nano to Large Tanks

Overstocking is the most common mistake in the hobby, usually one “just one more fish” at a time. Bioload, adult size, temperament, and swimming room matter more than a simple headcount.

Nano Tanks (Under 30 Gallons): Two small fish is a realistic ceiling for 10–15 gallons; 3–4 for 20–30 gallons. Good picks: ocellaris clownfish, royal gramma, gobies, six-line wrasse.

Larger Tanks (75+ Gallons): Tangs generally need 75–100+ gallons, dwarf angelfish 55+, and large angelfish 100–300+ gallons depending on maturity.

Avoiding Aggression: Add peaceful species first and territorial ones (tangs, angelfish, dottybacks) last, and break up sightlines with rockwork.

Feeding: Feed only what fish finish in 2–3 minutes; high-metabolism swimmers like tangs and anthias do better with smaller, more frequent feedings.

---

Water Changes: How Much, How Often, and Why Twice a Month Beats Once

No skimmer, refugium, or dosing routine fully replaces physically swapping old water for fresh. The real question is how much and how often — and less at a time, more consistently, wins.

How Much: Aim for roughly 10–15% every one to two weeks, working out to about 20–30% of total volume over a month.

Why Split It: Two smaller changes two weeks apart cut the swing in salinity, alkalinity, calcium, and temperature roughly in half compared to one big change — corals respond better to a flat line than a swing.

Consistency Wins: A reliable 10% change every other week outperforms an ambitious 25% change that only happens when you remember.

Tools That Help: An RODI unit, a mixing container, a powerhead for mixing salt, a gravel vacuum, and a refractometer make the process easy and repeatable. Plan your mixing equipment and routine with the full reef-tank water-change guide.

---

Algae ID Guide: Hair Algae, Bubble Algae, Diatoms, Cyano & Dinoflagellates

Almost every reef tank goes through an algae phase, and the fix is completely different depending on what you’re actually looking at.

Green Hair Algae: Driven by excess nutrients and mismatched lighting; manually remove and fix the underlying nutrient levels, or it keeps coming back.

Bubble Algae: Never crush it in the tank — twist and detach at the base and lift it out before it ruptures; emerald crabs help as a supplement to manual removal.

Diatoms: A fine brown dusting common in new tanks, feeding on silicate; often resolves on its own as a tank matures, or switch to RODI water.

Cyanobacteria (Red Slime): Driven by low flow and nutrient imbalance; lifts off easily with a turkey baster, but improving flow and water change consistency is the real fix.

Dinoflagellates: The most stubborn of the group — combine a 3–4 day full blackout with nightly food-grade hydrogen peroxide dosing, and fix the underlying nutrient imbalance.

Bryopsis: The one most often mistaken for hair algae, and the mistake matters because the treatment is completely different. Bryopsis grows in flat, feathery fronds that look like tiny fern leaves or pine branches, rather than the loose round strands of hair algae. Hold a strand up and look at its shape: if it is feathered along a central stem, it is Bryopsis. Manual removal alone almost never works and neither do most clean-up crew animals. Raising magnesium to roughly 1600 ppm over a week or a course of fluconazole are the two approaches that actually clear it.

Turf algae: A short, dense, stubbly green carpet that grips rock so tightly it feels like sandpaper and does not pull away in strands. It is far more stubborn than hair algae because the holdfast sits below the rock surface. Most grazers will not touch established turf. The reliable fix is removing the affected rock, scrubbing it dry, and correcting nutrients before it re-establishes.

Lobophora: A brown encrusting algae that grows in flat overlapping fans or blades, often creeping up rock and over the base of corals. It is increasingly common and frequently arrives on new frag plugs. It smothers coral tissue from the base upward, so remove it mechanically as soon as it appears and check the underside of every new plug.

Cotton candy algae: A stringy white to pale pink cottony growth, sometimes described as looking like spun sugar or wet tissue draped on rock. It spreads fast in low-flow areas and is genuinely difficult to remove by hand because it tears rather than lifts. Improve flow, siphon what you can, and be patient.

Coralline algae: The one on this list you want. Hard, crusty, and pink to deep purple, it encrusts rock, glass and powerheads in a mature tank and is a sign the system is stable. It does not harm corals and it should not be removed except from the viewing panes. New reefers regularly mistake it for a problem and scrub it off, which is a mistake worth avoiding.

---

Clean-Up Crew 101: Snails, Hermits, Starfish & Algae-Eating Fish

A reef tank without a clean-up crew is a full-time job for you instead of a shared one. Building the right crew in the right numbers makes everything else easier.

Snails: Turbo and astrea snails handle film and hair algae; cerith and nassarius snails work the sand bed — add snails first, once diatoms appear.

Hermit Crabs: Roughly one per gallon as a starting point; keep spare shells on hand so they don’t kill snails for their shells.

Starfish: Brittle stars are reef safe scavengers; true sand-sifting stars need a large, mature sand bed and often starve in home tanks.

Grazing Fish: Lawnmower blennies and yellow or kole tangs are strong algae grazers, though results vary fish to fish.

Timing: Wait for diatoms to appear as your signal to start, then build the rest of the crew in layers, topping off every 6–12 months.

---

Reactors Demystified: Biopellet, GFO & Carbon (and When You Actually Need One)

A reactor is just a small container that pumps tank water through a filter media, giving it far more consistent contact than tossing media loose in a bag.

Biopellet Reactors: Feed bacteria that consume nitrate (and some phosphate) as they multiply; pair with a skimmer, and expect 4–8 weeks to fully colonize.

GFO Reactors: The standard fix when phosphate specifically is high — binds phosphate directly, but needs replacing every 4–8 weeks and should be dosed in gradually.

Carbon Reactors: Doesn’t touch nitrate or phosphate, just pulls dissolved organics and tannins for clearer water; exhausts quickly, needing replacement every 1–2 weeks.

When You Need One: None are day-one requirements — reach for GFO or biopellets when test results show a persistent problem, not just because the equipment is available.

---

Live Rock vs. Dry Rock: Pros, Cons, and the Hybrid Method

Every reef tank needs rock — the question is whether it comes straight from the ocean as live rock, or bone-dry and built up from scratch.

Live Rock: Arrives with bacteria, coralline algae, and real biodiversity, cycling a tank in as little as 2–3 weeks — but it’s also how most hitchhikers (aiptasia, bristle worms, mantis shrimp) enter a tank.

Dry Rock: Starts completely sterile with zero hitchhiker risk and full aquascaping control, but cycling takes 6–8 weeks or more without help.

The Hybrid Method: Build roughly 70–80% of the aquascape from dry rock, then seed it with 20–30% cured live rock — most experienced reefers land somewhere in between, cycling in about 4–6 weeks.

---

Reef Dosing Explained: 2-Part, 4-Part, Kalkwasser & the Moonshiner’s Method

Once a tank has real coral biomass, water changes alone often can’t replace calcium and alkalinity as fast as corals consume them — that’s when dosing enters the picture.

When to Start: If alkalinity or calcium measurably drops between water changes even though your routine hasn’t changed, it’s time to dose. Test your actual daily consumption before calculating a dose.

Two-Part & Four-Part: Two-part covers calcium and alkalinity in a matched ratio; four-part adds dedicated magnesium and trace element bottles for a more complete, mature-tank routine.

All-in-One & Kalkwasser: Tropic Marin All-For-Reef covers all four in one bottle for simplicity; kalkwasser (mixed into your ATO reservoir) is an old-school way to add calcium and alkalinity together.

Foundation First: Whatever method you choose, keep consistent bi-weekly water changes underneath it — dosing replaces a handful of elements, but a water change resets your whole water chemistry.

---

Copepods 101: Tigger Pods, Tisbe, Apocyclops & the Phytoplankton Connection

Copepods quietly clean up detritus and move nutrition from the bottom of the food chain up to your fish and corals — a tank with no visible pod activity is missing a layer of biology nothing else replaces.

Phytoplankton: The base of the chain — it feeds copepods directly, which in turn feed fish and corals that eat the pods.

Tigger Pods: Larger, swim through open water, loaded with lipids — an easy target for planktivorous fish.

Tisbe & Apocyclops: Smaller, prolific breeders that crawl on rock and sand, ideal live food for small mouths like mandarins and gobies.

Healthy Indicator: A thriving pod population — visible at night, active hunting behavior, a mandarin finding its own food — is a sign of a well-balanced tank.

---

Common Reef Tank Pests: Aiptasia, Asterina, Vermetid Snails & Hydroids

Even a carefully aquacultured, well-quarantined tank can end up with pests sooner or later. None are usually an emergency, but all are easier to handle early.

Aiptasia: Chemical treatments (Joe’s Juice) kill what you can see; Berghia nudibranchs — which eat nothing but aiptasia — are the closest thing to a permanent fix.

Asterina Starfish: Mostly harmless detritivores, though some eat coral tissue; a harlequin shrimp will systematically clear a population if damage shows up.

Vermetid Snails: Their sticky mucus nets irritate coral tissue — remove manually or seal the tube opening with superglue to starve them out.

Hydroids: Fuzzy growths with a genuine sting; physical removal and a peroxide dip on affected rock handle most infestations, with a lynx nudibranch as a dedicated predator.

---

Spot Feeding Corals: How, When, and Why It Matters (Plus Amino Acids)

Spot feeding delivers food directly to individual coral polyps rather than broadcasting it and hoping — one of the more noticeable upgrades once a tank’s basics are dialed in.

Best Candidates: Corals with larger mouths and visible feeder tentacles — hammers, frogspawn, torches, acans, and Duncans — respond especially well.

How To: Turn off flow, load a syringe with tank water and food (Reef-Roids, BeneReef, mysis), and release it directly over open polyps.

Frequency & Timing: Once or twice a week is a good starting point, ideally in the hour around lights dimming in the evening, though consistency matters more than the exact hour.

Amino Acids: Dosing aminos supports polyp extension, coloration, and tissue recovery — start light, since overdoing it can fuel a cyanobacteria bloom.

---

Reef Tanks as Therapy: What the Science Says About Aquariums, Blood Pressure, and Mental Health

A reef tank isn’t just decor — a growing body of research suggests watching an aquarium can measurably lower blood pressure, slow heart rate, and ease anxiety, with the effect growing stronger the more life is in the tank.

The Exeter/Plymouth Study: A 2015 study found viewing an aquarium display reduced blood pressure and heart rate and improved mood, with more fish producing a bigger effect.

Clinical Settings: Aquariums in dental waiting rooms reduced anxiety, and a Purdue University trial found Alzheimer’s patients near tanks ate 17% more food and showed less agitation.

Why a Reef Tank May Amplify It: More movement, more color, and a living system that’s always changing plausibly makes a mature reef tank a higher-dose version of the same calming effect.

Note: This is general information, not medical advice — talk to your doctor about managing blood pressure or anxiety.

---

Soft Corals

Soft corals are among the most forgiving corals in the hobby, making them a great starting point for beginners. They tolerate a wide range of water conditions and don’t demand the pristine chemistry that stony corals need.

Lighting: Low to moderate lighting suits most soft corals, and many species (Xenia, Zoanthids, Green Star Polyps) adapt well across a wide range of intensities. If your lighting runs strong, start new arrivals lower in the tank and work them up gradually.

Water Flow: Low to moderate, indirect flow works best. Enough movement to keep detritus from settling, but not so much that the coral can’t stay open.

Feeding: Soft corals get most of their energy from photosynthesis and are comfortable in nutrient-richer water than other coral types. Occasional target feeding can speed up growth, but it isn’t required for survival.

Ideal Temperature: 72–78°F, with stable parameters mattering more than any single number.

---

LPS Corals (Large Polyp Stony)

LPS corals — Hammer, Torch, Frogspawn, Favia, Chalice, Duncan, and similar species — bring fleshy, dramatic movement to a reef tank and are a natural step up from soft corals.

Lighting: Moderate to low PAR is typical, generally in the 50–200 range depending on species. Euphyllia types (Hammer, Torch, Frogspawn) are especially tolerant of lower light.

Water Flow: Gentle, indirect flow. Direct, high-pressure flow causes constant polyp retraction and stresses the tissue — aim for enough movement to deliver food and prevent debris buildup without blasting the coral.

Feeding: LPS corals are active feeders and will extend feeding tentacles when they sense food in the water. Target feeding meaty foods (mysis shrimp, reef-specific coral foods) 1–3 times a week noticeably improves growth and color.

---

SPS Corals (Small Polyp Stony)

SPS corals — Acropora, Montipora, and similar genera — are the most demanding corals in the hobby, but reward stable, experienced reef keepers with fast growth and vivid color.

Lighting: High PAR, generally 200–400 depending on species and depth in the tank. Consistent photoperiods (8–12 hours) with gradual ramping are important.

Water Flow: Strong, turbulent flow is essential. SPS corals come from high-current reef environments and need that movement to bring nutrients in and sweep waste away.

Water Chemistry: This is where SPS corals are unforgiving — stable calcium, alkalinity, and magnesium are non-negotiable, and low nitrate/phosphate levels are important to prevent algae issues.

Feeding: Mostly photosynthetic, but supplemental feeding of fine zooplankton or amino acids helps growth and coloration, especially in low-nutrient systems.

---

Mushroom Corals (Corallimorphs)

Mushroom corals are some of the easiest and fastest-growing corals available, and a favorite for hobbyists who want a lot of color and movement without much fuss.

Lighting: Low to moderate, generally 50–150 PAR. Too much light causes bleaching or shrinking; too little dulls their color and slows growth.

Water Flow: Low flow is best. Strong current keeps mushrooms from fully extending and can even dislodge them from their footing.

Feeding: Feeding isn’t strictly necessary since mushrooms get most of their energy from photosynthesis, but occasional spot feeding (brine shrimp, Reef Roids, or similar) noticeably speeds growth and deepens color. Turn off flow before feeding and give the coral time to fully engulf the food.

Placement: Mid to lower tank, on rock or substrate where their foot can get a solid grip.

---

Water Flow

Water flow is one of the most important — and most overlooked — factors in a healthy reef tank. It’s not just about making the water “move.” Flow delivers food and oxygen to your corals, carries waste and excess nutrients away from them, helps with gas exchange at the surface, and evenly distributes heat and trace elements throughout the tank. Corals that don’t get enough flow develop dead spots where waste settles and algae takes hold; corals that get too much, or the wrong kind, can’t stay open to feed.

What Creates It: Flow in a reef tank generally comes from three sources — your return pump (which moves water from the sump back into the display), powerheads (submersible pumps placed inside the display for direct circulation), and wave makers or controllers that pulse multiple powerheads to vary the pattern over time.

Laminar vs. Turbulent Flow: Laminar flow is a single, constant stream in one direction — easy to create with one powerhead, but it leaves dead zones behind rocks and corals where debris collects. Turbulent flow is random, chaotic movement created when two or more currents collide or bounce off rock and coral. It’s what you actually want in a reef tank: turbulence keeps the whole water column moving so nothing settles anywhere.

How Much Flow You Need: A common starting point is 10–20x your total tank volume in gallons per hour (GPH) for a mixed reef, and more for SPS-dominant tanks. As a rule of thumb, aim to turn over your entire display volume through return flow alone 5–10 times per hour, then add powerheads for the turbulence on top of that.

Our Recommendation: Use at least two powerheads placed on opposite ends or corners of the tank, angled so their currents collide rather than run parallel — this is what generates the turbulence corals thrive in. Match your flow to what’s actually in the tank: soft corals and LPS want gentle, indirect movement, while SPS corals need strong, randomized current. Watch how your corals respond — tissue that won’t stay open usually means too much direct flow, while visible detritus settling on a coral usually means not enough. As your tank matures and corals grow, flow patterns change, so it’s worth rechecking placement every few months rather than setting it once and forgetting it.

---

Lighting

Lighting is what makes a reef tank possible in the first place — the vast majority of corals host photosynthetic algae (zooxanthellae) in their tissue, and that algae needs light to produce the energy corals depend on for growth and color. Get lighting wrong and corals will bleach, fade, or slowly starve even if every other parameter is perfect.

PAR (Photosynthetically Active Radiation): PAR measures the usable light energy corals can actually convert into food, and it’s the number that matters far more than watts or lumens. As a general guide: soft corals and mushrooms do well around 50–150 PAR, LPS corals around 100–200 PAR, and SPS corals need 200–350+ PAR. Many tanks are also categorized simply as low light (30–50 PAR), medium light (50–150 PAR), or high light (over 150 PAR).

Spectrum: Corals rely mostly on blue and violet wavelengths (roughly 400–500nm) for photosynthesis. A balanced spectrum — heavy on blue and violet with some white mixed in — supports both healthy growth and vibrant coloration, which is why most reef-specific LED fixtures are tuned this way rather than running plain white light.

Photoperiod: Most reef tanks run 8–12 hours of full-intensity light per day, with a gradual ramp-up and ramp-down on either side to mimic sunrise and sunset. That ramping isn’t just cosmetic — it reduces stress on corals and fish compared to lights snapping on and off at full power.

Our Recommendation: LED fixtures are the standard today for good reason — efficient, no bulbs to replace, and fully controllable so you can dial in intensity, spectrum, and schedule per coral type. Whatever fixture you’re running, acclimate every new coral slowly: corals shipped to you have spent a day or more in the dark and can bleach within a day or two if dropped straight under strong light. Start new arrivals lower in the tank or at reduced intensity, and increase gradually over one to two weeks. When in doubt, under-light rather than over-light — it’s much easier to recover a coral that’s a little dim than one that’s been burned.

---

Zoanthid & Palythoa Care

Care Level: Easy (great for beginners)  |  Lighting: Low–Moderate  |  Flow: Moderate  |  Placement: Low to mid tank

Zoas and palys are colonial polyps that spread quickly and pack a ton of color into a small footprint, which is why they’re one of the best first corals for a new reefer. The two things that trip people up: overly strong flow that keeps polyps closed, and pests (nudibranchs, zoa-eating spiders) that hitchhike in on new frags. Dip every new frag before it goes in your tank, and introduce light gradually – a zoa that looks “melted” a day or two after arriving is almost always reacting to a big jump in light or flow, not disease.

Keep them thriving: target-feed with TUG Phyto Plankton (we cultivate it in-house) a couple times a week to boost color and polyp extension, and mount new frags securely with CorAffix Coral Glue.

---

SPS Coral Care (Acropora, Montipora, Birdsnest & More)

Care Level: Advanced  |  Lighting: High  |  Flow: High, turbulent  |  Placement: Upper tank

SPS (small polyp stony) corals are the least forgiving of parameter swings, so they’re best added once your tank has been stable for at least 6 months. Calcium, alkalinity, and magnesium need to stay in a tight range week to week – the goal is stability, not perfection. Acclimate new SPS to your lighting slowly over 2–3 weeks; a rapid jump in PAR is the most common reason a healthy-looking frag bleaches out after arrival.

Keep them thriving: mount frags rock-solid with Tunze Coral Gum Fast Epoxy so they can’t shift in high flow, and feed fine particulates like TUG Phyto Plankton to support coloration.

---

LPS Coral Care (Hammer, Torch, Frogspawn, Favia, Chalice & More)

Care Level: Easy–Intermediate  |  Lighting: Moderate  |  Flow: Moderate, indirect  |  Placement: Low to mid tank

LPS (large polyp stony) corals are a natural step up from softies – big, showy polyps that are far more forgiving than SPS. The main thing to plan for is spacing: hammers, torches, and frogspawn extend long sweeper tentacles that will sting anything they touch, so give each colony 4-6 inches of open water on every side. Moderate, indirect flow keeps the polyps fully extended without blasting them shut.

Keep them thriving: occasional target feeding with TUG Phyto Plankton encourages fuller extension and better color, and CorAffix or Tunze Coral Gum Fast Epoxy will keep frags anchored while they heal in.

---

Soft Coral Care (Leathers, Mushrooms, Clove Polyps & More)

Care Level: Easy  |  Lighting: Low–Moderate  |  Flow: Moderate  |  Placement: Anywhere

Softies are the most forgiving corals in the hobby and a great way to fill out a new tank while it matures. The one thing to watch for is allelopathy – some soft corals release chemical compounds that can irritate neighboring corals, so give them a little breathing room and run fresh activated carbon periodically to keep the water clean.

Keep them thriving: mount new frags with CorAffix Coral Glue and feed TUG Phyto Plankton weekly to support growth.

Visiting or living in the Florida Keys? Check out our Key West Coral and Key West Reef Tank pages for local pickup, sourcing, and stocking info.

Looking to buy local live rock? Check out Florida Keys Live Rock and Live Rock From the Florida Keys for sourcing details and current stock.

Choosing where to buy matters as much as day-to-day care. Our comparison guide covers WYSIWYG versus stock photography, shipping costs and thresholds, and how to read a live arrival guarantee before you order: Where to Buy Coral Online.