The Best Corals for the Top of a Reef Tank - Aqua Life Hub (2024)

A reef tank is a living piece of art. When things are going right, there is nothing quite as stunning as a living coral reef (as long as you can automate things well enough to keep everything stable). Of course, you have to arrange your corals in such a manner that both makes artistic sense, as well as taking into consideration the health of your corals. Below are some of the corals that are best for the top of a reef tank.

Considerations for Corals at the top of your tank

Locations in your tank are not just for show--different positions in the tank will also getting varying degrees of light, flow, and open water in which to expand upwards. Each one of these factors are important to keep in mind when determining what coral you want to put at the top of your tank.

In many ways, the top of a reef tank is the hardest area for a new reefer to fill out. Experienced reef tank owners will often fill up the top of their rock structures with SPS corals: Acropora and montipora in particular. If you are to the point where you can keep thriving acropora colonies, this advice will probably be too simple for your needs. Although, maybe there will be something on this list that catches your eye!

Lighting

The biggest difference between the top of your rockwork and the corals sitting on your sand-bed is the amount of light they receive. Light is often measured in Photosynthetic Active Radiation (or "PAR" for short). Most corals are photosynthetic, so this is a very useful measurement. The higher the PAR, the more light that spot in the tank is receiving.

Light very quickly loses its intensity as you go lower in the tank. It's not a straight linear loss either: If you have 800 PAR at the top of your tank, you might have 600 PAR 6 inches beneath the surface, and 450 one foot below the top of the water. This is a key consideration to keep in mind when selecting corals for the top of your tank.

Not every coral is tolerant of the same levels of lights. Some corals are naturally from deeper in the ocean, and therefore do best under lower lights. What we are looking for are the corals that will do best under the most intense lighting in your tank (although if you aren't keeping any SPS corals, you may still have a reasonable PAR level even at the top of your tank--something to keep in mind!).

Flow

This one is also common sense. You will likely have more flow at the top of your rocks than on the sandbed, as the flow from your powerheads will be broken up by your rockwork and other corals. If the coral is at the very top of the rocks, leaning into the water column, it will need to withstand the highest amount of flow in your tank. Soft corals, such as zoanthids or mushrooms, do not generally fit this bill. Of course, you can adjust this a bit, by placing the corals closer or further away from the powerhead. You can also get a gyre powerhead, which tends to give a more even distribution of flow.

Growth Patterns

Your little coral frag is going to grow! Well, we all sure hope that our frags will grow. You need to understand how the coral is likely to grow, and plan accordingly. Corals that grow straight up are often best on the top of the rockwork, if they can withstand the flow and lighting at the top. Otherwise, they tend to crowd everyone else's space.

Best Corals for Top of Rocks in a Reef Tank

Without further ado, here is our list of top dogs for the top of your reef tank:

Acropora Coral

This wouldn't be a proper list without putting Acropora first, now would it? Beginner reef tank owners should not get acroporas (or their close cousins Anacropora), as they are notoriously fickle and unlikely to survive a new reef tank as someone new to the hobby learns how to accommodate the chemistry swings that are inherent in this hobby.

However, acropora corals truly are the king of the top of a reef tank that can support them. Acroporas love high light, high flow, and grow upwards. There is unlikely to be anything in your tank that needs more light than a large acropora colony. If you are to the point of being able to keep acros, then what are you waiting for?

Will Thomas [CC BY]

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Birdsnest coral is an SPS (small polyp stony) coral that is often considered the "baby's first SPS" coral grand champion. Birdsnest is generally considered to be the SPS most tollerant of water chemistry changes, and most likely to thrive under less than perfect circ*mstances. This does not give license to have poor water quality, but if you are a newer reefer with some thriving softy corals, this is a fantastic first step into SPS corals.

Not only are they easier, but they also staisfy the space requirements for the top of your reef tank. Birdsnest coral grows mostly upwards, with a distinctive branching look that gives it the "birdnest" name.

Seriatopora is not as tollerant of extreme lighting and flow as other SPS such as Acropora or Pocillopora (discussed below), but if you know you aren't going to be getting the other SPSs that require the most light, you can reduce your overall lighting in your tank and happily put birdsnest on the top of your rocks.

Do not place Birdsnest right next to a powerhead, as they prefer "medium" flow. As the colony gets bigger, it will want more flow to get to the center of the colony, so try to account for that in your initial placement.

National Park of American Samoa [Public domain]

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Pocillopora ranks somewherre between Acropora and Seriatopora when it comes to difficultly level. However, it probably falls closer to the easier side of the scale. If you've been successful with birdnest, you can consider picking up pocillopora to fill in the top of your reef tank as well.

Pocillopora is not the most popular SPS coral, but they are extremely attractive, and give the distinct look of a true coral reef.

As is fitting with a coral that we are looking to put at the top of the tank, Pocillopora can thrive under medium to high lighting, and medium to high flow.

One of the fun things about this coral is "polyp bailout." On occasion, your Pocillopora may decide to ditch polyps into the water, and you'll find new colonies growing elsewhere in the tank. While fun at first, this may become annoying over time if you have to dig them off the rocks to put in something else in that location.

Nhobgood Nick Hobgood [CC BY-SA]

Never fear, soft leather coral fans, not everything on this list is an SPS coral. The soft coral we consider best for the top of rockwork in a reef tank is Nephthea Leather Coral. This coral has a distinct look, and was at one point endangered in the wild. It is now extremely popular in the reef tank hobby due to its distinct look and easy care requirements.

In addition, it is one of the few soft corals that have a similar "upward and outward" growth pattern so common to SPS corals. This is one of the reasons it is a fantastic choice for the top of your rocks.

This coral enjoys high flow (a huge plus in favor of the top of the rockwork) and medium lighting. It will not thrive under intense lights, but may be alright under simply "high" lights, but you'll need to acclimate Nephthea correctly for the best chance at success.

Aguleo [CC BY-SA]

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I'm going to be completely transparent here. LPS corals in general are not a good candidate for the top of a reef tank. Most LPS prefer low light, and low to medium flow, due to their fleshy body not enjoying being pressed against the skelleton by the high flow.

That being said, candy cane corals are the best LPS coral for the top of the reef tank if you simply must place an LPS up higher. These corals prefer medium light and medium flow. If you are trying to put them at the top next to an acropora, just forget it. Candy canes are fine to epoxy down to top of rockwork where you have moderate overall lightning levels.