Thinking about starting a reef tank for the first time? In that case, you’ll need to understand the intriguing world of large polyp stony coral care.
Large polyp stony corals are just as striking in their alien beauty as small polyp stony corals. Instead of delicate branching structures large polyp stony corals form a thick base with a meaty polyp that’s the star attraction.
But how different are large polyp stony corals from their small polyped cousins? And are they all too difficult for beginners to attempt?
What are LPS Corals?
There are two abbreviations commonly used in the reefkeeping world that you’ll want to know better: LPS and SPS. LPS stands for Large Polyp Stony while SPS refers to Soft Polyp Stony corals. As you might have guessed, they describe the appearance of the two main groups of stony corals. There are also Soft Corals, which don’t create a calciferous base to grow from.
LPS corals can be seen as an evolutionary (and difficulty level) bridge between soft corals and SPS corals. Like nearly all shallow water corals they also have photosynthetic zooxanthellae living within their tissues.
In a classic example of mutually beneficial symbiosis, these single celled algae receive nutrients and shelter from the coral in exchange for a share of the sugars they create through photosynthesis.
Many corals can live entirely off of their zooxanthellae and a dusting of organic matter. But some LPS are quite hungry and grow faster and more robust when fed on occasion.
LPS Corals are more frequently aggressive compared to SPS and soft corals. The small polyps and slower growth rate of SPS corals tend to result in more passive behavior.
But LPS run the gamut from using long sweeper tentacles to sting distant neighbors to releasing poisonous compounds that halt the growth of competitors. Some even extrude mesenterial filaments (coral guts) if they come in contact with a close competitor. These allow the coral to literally digest its rival!
A few LPS (Disk Coral) also have toxic mucus that will burn an enemy they come into contact with. In short, it’s very important to understand how each coral defends its territory and to keep them separate at all times. You wouldn’t think corals are competitive considering they mostly sit there, slowly growing and eating. But the coral reef is actually one of the most dynamic environments on the planet.
SPS corals, on the other hand, tend to be even less tolerant of poor water quality. Even the beginner friendly species are best attempted only after you have the basics of coral care down pat. Fortunately, if you’re reading this, you’ll have a solid understanding of how to care for both types by the time we’re finished!
Caring for LPS Corals
No coral aquarium is truly simple. Except for some of the easiest soft corals like Kenya Tree Coral, which grow like invasive weeds, there will always be some level of balancing required. That said, LPS corals are more beginner friendly than SPS corals. They tend to need less light and are more forgiving in terms of current and water conditions.
Still, we want to provide them with the best conditions possible. And in order to do so, we need to be familiar with stability. Stability is the key to succeeding at keeping any stony coral.
Despite the pounding waves, the marine reef is an extremely stable environment, chemically speaking. Ammonia, nitrate, and other parameters are continually low, while magnesium, calcium, strontium, and other essential elements are always around in just the right concentrations.
Temperatures go through slow, predictable seasonal shifts and the currents likewise are predictable to entirely stable. It takes thousands or even millions of years for most significant changes to happen (a major reason why climate change is doing tremendous harm to modern reefs).
In an aquarium, missing water changes, allowing too much water to evaporate, overfeeding, and other instances can cause the parameters to fluctuate drastically in a short time. Corals can’t handle the stress of sudden water chemistry shifts. So many reef keepers automate dosing of calcium and other elements.
The major elements we need to monitor are calcium, magnesium, and strontium. Corals also use iodine, iron, and other trace elements but these are present in any complete marine salt blend and get replenished when you perform water changes.
Calcium is extremely important as it forms most of their aragonite skeleton (calcium carbonate – CaCO₃). Magnesium affects not only pH stability but also forms part of the biological chain of events that allow corals to uptake calcium from the water. Strontium is less well understood but most corals seem to uptake trace amounts and do poorly when it’s unavailable.
Nitrate and Phosphate are two compounds that are somewhat tricky for reef aquarists because in high levels they are pollutants. Nitrate is toxic in concentrations of 20ppm or greater to most invertebrates.
Phosphates in high levels fuels the growth of algae which can grow much faster than any coral. Coralline algae and macroalgae can outcompete corals for living space and even grow over top of them.
However, all corals need trace amounts of both because they are important nutrients for their zooxanthellae. Many beginner-friendly LPS, SPS, and soft corals thrive because they actually prefer elevated levels of nitrate. In a new aquarium, nitrate levels can be higher as the biological cycling process hasn’t finished. But in a mature reef tank, many beginner corals may actually suffer in water that’s too pure.
Therefore, it’s always best to find a balance between purity and slight nutrient accumulation. Use the following parameters to ensure your corals can extract all that they need from the water column!
General LPS Coral Water Conditions:
- Temperature: 72-78℉
- pH: 8.0-8.24
- Specific Gravity: 1.023-1.025
- Alkalinity: 9-12 DKH
- Calcium: 350-450 ppm
- Magnesium: 1200-1350 ppm
- Nitrate: 1-10ppm
- Phosphate: 0ppm
There may be some slight variation for particular LPS coral species. But these parameters are ideal for the vast majority!
Many LPS corals also do well with occasional feedings. SPS, soft, and many LPS corals can do just fine with nothing but strong light and dissolved nutrients. But as a whole, LPS corals are the ones you should feed most often. Many have a large mouth that you’ll see them slowly shove food into.
Since corals eat fairly slow, it’s better to feed them at night. Not only are the sweeper (feeding) tentacles more likely to be extended but fish are likely to be sleeping then. Day feedings can be an issue if your fish are hungry since they will easily pluck food out of the grasp of your SPS corals.
Brine shrimp, mysis shrimp, coral pellet formulas, and chunks of shrimp or fish for corals with large enough mouths are the best things to offer. Combined with the nutrients they absorb from their tank mates, you are all but guaranteed to see rapid growth.
8 Best LPS Corals for Beginners
LPS Corals can be somewhat demanding because they need the stable conditions that a mature, well cycled aquarium provides. That said, there are a few LPS species that will thrive through the occasional hiccups that happen as you learn how to care for them!
Hammer Coral
Hammer Corals have oddly shaped tentacles; once you’ve seen one for the first time, it’s clear how they get their name. The tentacles are shaped either like bulbous hammers or they can have a more broad T spread to them.
In terms of lighting, Hammer Corals do well in moderate to low light conditions. In fact, you may see them extend their polyps and tentacles much further. In high light environments they tend to contract substantially into themselves. Since more light can bring out the vivid colors in this species so moderate light provides the best balance.
Like all Euphyllia corals they also prefer moderate water flow; enough to keep their tentacles jostling about. Their active nature and grasping tentacles make them a real show stopper for any reef aquarium.
Hammer Corals don’t really require food. They will accept small pieces of food but do very well with enough light and current that provides a steady stream of organic matter. Feeding does tend to boost their growth rate, however.
Hammer Corals are one of the more aggressive species. Euphyllia corals in general (Torch, Hammer, and Frogspawn) have long sweeper tentacles that give them 6-8 inches of added reach. If you don’t space them properly they will damage or kill their neighbors.
That said, Euphyllia corals do tend to get along with one another. Hammer and Frogspawn are the most likely to get along well and you can also keep multiple Hammer Corals together.
- Common Names: Hammer Coral
- Scientific Name: Euphyllia ancora
- Origin: Pacific Ocean
- Temperament: Aggressive
Trumpet Coral
Candy Cane or Trumpet Coral are one of the most common LPS corals for beginners to find at your local fish store. They are both inexpensive and not especially aggressive; two great traits for your first coral!
Interestingly, Trumpet Corals aren’t nearly as variable in appearance as other corals when shifting them around. Some species tend to brighten or darken quite a bit depending on the lighting and angle. Trumpet Corals will look more or less the same, making aquascaping with them easier!
Trumpet Corals are very undemanding in terms of lighting and flow. Low light and low flow are just fine. Enough flow to keep mucus and debris from accumulating is all they need so they are great residents for the bottom of your reef tank.
They are considered semi-aggressive because their sweeper tentacles are fairly short. That said, Trumpet Coral will definitely try to sting anything they can reach so don’t place them too close to anything.
Trumpet Corals do enjoy being fed as well, sometimes as often as 2-3 times per week. A few pieces of formulated coral pellets, brine or mysis shrimp, and similarly sized items are all they need.
- Common Names: Trumpet Coral, Candy Cane Coral
- Scientific Name: Caulastrea furcata
- Origin: Pacific Ocean
- Temperament: Semi-Aggressive
Torch Coral
Torch Coral are a great place to begin keeping LPS corals. Kept in the moderate to strong currents they prefer, their tentacles wave like a torch, giving them their name. Bright lighting will bring out nicer colors in your Torch Coral but they do just as well in medium and even low light conditions.
Like all members of the genus Euphyllia, Torch Corals are very aggressive. Their sweeper tentacles give them 6 to 8 inches of reach and will sting their neighbors relentlessly at night. So provide them with plenty of space and ensure that the currents don’t cause their sweepers to waft onto defenseless tank mates.
That said, most Euphyllia corals will get along with one another. Torch and Frogspawn Coral (Euphyllia divisa) tend to be the most compatible. Hammer Coral (Euphyllia ancora) are sometimes problematic, though. You’ll simply have to experiment if you wish to keep several Euphyllia in close contact.
Torch Corals aren’t as hungry as some other LPS corals. They do benefit from direct feeding and the boost in nutrition will help them grow faster. But they can live solely off of their zooxanthellae in the right conditions.
Combined with organic detritus from fish and other tank mates and you have a coral that’s very easy to maintain once established. The long, luxurious tentacles make Torch Coral appealing for Clownfish to host if there are none of their preferred sea anemones around.
- Common Names: Torch Coral, Pom Pom Coral, Trumpet Coral
- Scientific Name: Euphyllia glabrescens
- Origin: IndoPacific Ocean
- Temperament: Aggressive
Acan Coral
Like many of LPS corals for beginners, Acan Coral are avid feeders once established. Once per week, you’ll want to offer them either pellets or thawed mysis shrimp to keep them healthy. Since they only need at the most 50 PAR of intensity Acans make great low light corals.
They can be conditioned to live in high light tanks but only if done so slowly. Acan Lords also love moderate to high flow and should be placed accordingly.
Acan Coral are very aggressive corals but only if kept too close to their neighbors. Since their sweeper tentacles only give them about an inch of added reach they can be kept closer to other corals than, say, Torch or Bubble Corals, which have 6-8 inches of reach.
Acan Corals also extend mesenterial filaments that will digest their neighbors as well so give them a few inches of space!
- Common Names: Acan Coral, Acan Lord, Acan Brain Coral
- Scientific Name(s): Micromussa (Acanthastrea) lordhowensis
- Origin: IndoPacific Ocean
- Temperament: Semi-aggressive
Bubble Coral
Bubble Coral are a lovely genus of easy to care for corals that are extremely unique looking. They are excellent low light corals as they depend on feeding more than their zooxanthellae. Bubble Coral only requires a gentle to moderate water flow; just enough to jostle the “bubbles” enough to remove debris and excess mucus.
They are an aggressive species as they deflate their bubbles at night and extend long sweeper tentacles, stinging anything that they can touch. So provide around 6 inches of space between your Bubble Coral and its neighbors.
The two main varieties have tentacles that are either round like grapes or more irregular in form. But both are extremely hardy once established.
Bubble Coral has a very uniquely shaped skeleton that needs to be handled very carefully. The edges are quite sharp and can cut right through the flesh of the coral if it comes in contact with another hard surface. This can lead to infection and possible death.
Even if your Bubble Coral ends up dying, don’t be too quick to toss it out. These corals are also very tenacious and have incredible regenerative abilities; a few specks of healthy flesh on a bare skeleton can come back over the course of months to form a small but stable colony once more!
- Common Names: Bubble Coral, Pearl Coral
- Scientific Name: Plerogyra sp.
- Origin: IndoPacific
- Temperament: Aggressive
Disk Coral
Disk Corals are typically green but may also be found in yellow, pink, purple, and other hues. Unlike nearly any other LPS coral, Fungia sp. are capable of moving, which you need to take into account when placing them! They can inflate their body tissues to catch the current and “sail” to a new location. Or they may simply drag themselves about. Disk Coral can cover up to 12 inches a day in this way.
While cute, this can be a real problem if your Disk Coral falls onto another species from above, inviting coral warfare. It’s recommended to keep them on the substrate where they can shift about to their satisfaction. If they encounter an aggressive species they will simply move away. Fortunately, Disk Coral are otherwise peaceful, though their mucus is poisonous to other corals they come in contact with.
Disk Corals prefer medium to high light, moderate water currents, and they do need to be fed semi-frequently. 2-3 times a week is ideal for them. Disk Corals use a mucus net and feeding tentacles to snare small invertebrates; mysis and brine shrimp are ideal prey. In the center of the disk is a large slit-like mouth capable of engulfing items as large as krill chunks.
Since Disk Coral mucus is poisonous to other corals, watch that the current doesn’t cause their feeding net to drift onto its neighbors.
- Common Names: Disk Coral, Tongue Coral, Fungus Coral
- Scientific Name: Fungia sp.
- Origin: IndoPacific
- Temperament: Peaceful
Brain Coral
There is quite a bit of variation among Brain Corals! They come in an assortment of colors and growth forms. Some are slow growing while others double in size quite quickly. But as a group they are easy to maintain and excellent LPS corals for beginners. Moderate to higher lighting along with at least moderate flow and good food is all they need to thrive.
The only real issue to be aware of is that these corals are both hungry and aggressive. In the evening/at night they extend long sweeper tentacles in search of small prey. These same tentacles are used to sting other corals that grow too close to them. It’s common to find nearby corals dying mysteriously for “no reason” since you will only see the sweeper tentacles in the dark.
Since they have a few inches of reach, you’ll need to provide a lot of space between a Brain Coral and its neighbors. They should be fed brine shrimp, copepods, and other small prey once or twice a week as well.
Fragging Brain Coral is also on the challenging side. They have shared corallite walls that have to be cut along, rather than into, to avoid causing too much damage. It’s better to let these corals bud on their own rather than propagate them yourself.
- Common Names: Brain Coral, Pineapple Coral, Moon Coral
- Scientific Name: Favites sp.
- Origin: Indopacific Ocean
- Temperament: Aggressive
Lobed Brain Coral
If you’re looking for a coral that’s fairly flexible in terms of its needs and placement, Lobed Brain Coral is an excellent choice. They prefer moderate lighting and don’t need much more than 100 PAR. These corals also come in a wide variety of colors and shapes; there’s no reason why you couldn’t keep several species in a single tank!
Lobed Brain Coral prefers a low to medium water current. When kept in environments with too much flow they will retract tight against their skeleton and may even recede entirely where they are getting battered by the current. These corals can also be kept along the aquarium bottom where the currents are weakest. But they still want some gentle flow to keep debris and mucus from accumulating on them.
Lobed Brain Corals are semi-aggressive. While they don’t have sweeper tentacles or poison attacks they will launch mesenterial filaments if kept too close to rivals. Just a small amount of space is all that’s required to keep their neighbors safe.
- Common Names: Lobed Brain Coral, Open Brain Coral, Lobo Coral
- Scientific Name: Lobophyllia sp.
- Origin: IndoPacific Ocean
- Temperament: Semi-Aggressive
