Knowing where to place coral in your tank really is a blend of science and art. It is something you master in time as you gain experience with all of the different types of coral. The color, size, environmental preferences, aggression, and even how fast the coral grows must be considered in order to identify a suitable location inside your tank. As a beginner, you may find yourself second-guessing the placement of new corals, and constantly moving a new coral can certainly do more harm than good.  

Things To Consider For Successful Coral Placement 

Matt drew up a list of 8 different things to consider when deciding where to place a coral so you can be confident that your coral is going to succeed and grow into the thriving colony you envision. 

1. Color

This is the art side of coral placement. Understanding how different colors mix together in your tank to create a cohesive aquascape really does go a long way in terms of the end result.  You can break it down as simple as placing complementary colors next to each other or grouping certain colors together. This is completely subjective too because what looks good to you, may not look so good to me but at the end of the day, it's your tank and that is what matters most. Consider the color of the corals in your tank and how they will grow together in the tank to create something that looks good to you. This is also something to keep in mind when shopping for new coral too; it's easy to end up with 10 corals that are all different shades of fluorescent green.

2. Growth Rate

A fast-growing coral needs more room to grow compared to a slower-growing coral.  If you have a large space you want to be filled with coral, a faster-growing coral species is probably a better choice for that particular location. Some corals do not like touching other corals so giving them plenty of room to grow is important.  Some coral grows up, some encrust or grow sideways, some corals grow out in every direction or sway back n forth in the current. 

3. Aggression

Some corals are aggressive and will attach other corals that come within their reach.  If you're dealing with a particularly aggressive coral with sweeper tentacles like a Galaxia or Torch, you have to be mindful of any coral placed within reach of those tentacles.  Placing LPS and SPS coral next to each other is often not the best combo either.  Do the necessary research to find out how aggressive a coral can be and place them accordingly. 

4. Flow Pattern

Some coral prefers lower flow, some like a medium flow, and some are at home in super-crazy high flow. This is typically based on the part of the reef they naturally inhabit where corals that grow up on the top of the rocks are constantly bombarded with waves and higher currents and corals stuck down on the seafloor or within the rock crevices are more protected from those currents. Some corals only grow in very calm lagoon situations. You will have these various flow zones in your reef tank and placing coral based on their flow requirements is very important to the long-term health of that particular coral. 

5. Lighting

Just like flow, different corals have different preferences for lighting.  High, medium, and low light conditions, all of which can be represented in your tank. Place corals in the right location based on their lighting requirements. Using a PAR meter to measure the light levels in your tank really is the ONLY way to know for certain how much light a coral is receiving and whether or not it's going to thrive. You can adjust the output level of your LED lights to accommodate different types of coral but once you set your light's output, you cannot change it. IN other words, create the lighting conditions for the corals you want to keep first, then only buy corals that will thrive within that range. 

6. Height

This is important because it is related to both the flow and lighting conditions. Corals placed on the top of the rocks, higher up in the tank, will get more light and likely stronger flow.  Coral placed in the middle and bottom is going to receive a medium to a low amount of light and flow. For example, a soft coral is generally at home towards the bottom of your tank whereas something like an Acropora or SPS coral will typically thrive on top of the rocks. 

7. Shadowing

Corals will create shadows as they grow and sometimes even block light from reaching corals growing below them. This is especially true with plating and branching corals.  A coral that grows in a spiraling plate outwards will certainly block light from anything growing below it.  Branching SPS corals will grow into a tight network, shadowing the corals below.  Think about the growth pattern and the shadows it may create as the coral grows. 

8. Placement Difficulty

This has to do with how difficult it will be to attach a particular coral to the rock.  Some rock surfaces are more porous than others, some are flat, and some are full of crevices. It's much easier to glue a coral frag into a crevice or porous rock surface compared to a smooth surface.  With a little patience, you can usually adhere coral frags to almost any place on the rocks, but sometimes this can also prove to be challenging and is certainly worth your thoughts. 

Useful Gear For Mounting Corals

In 90% of the cases, using cyanoacrylate coral glue is the best way to mount a coral frag. It cures underwater and will adhere to both the coral frag and rock with ease. Keeping plenty of coral glue on hand is always recommended.  Epoxy can also come in handy when you just can find a good crevice or spot to attach a frag. Epoxy is great for building support or filling in areas where glue just won't cut it.  Propagation tools including forceps and coral shears are also valuable because it allows you to move delicate corals without damaging tissue and trim away frag plugs or dead skeleton. 

How To Anchor A Coral In Your Tank

With a new coral, you have the options of leaving the coral mount attached, trimming the coral mount, or removing it altogether before attaching it to your rocks. While frag mounts can be unsightly, they are sometimes necessary to provide support for very small fragments of coral or pieces of encrusting corals. This frag mount removal or trimming really is up to you as a hobbyist but most experienced reef tank owners will try to remove coral mounts before anchoring the coral to the aquascape whenever possible. 

Boiled down, there really are only two ways to anchor a coral to your aquascape. You can either wedge it into a rock crevice or use a coral adhesive to glue it in place. Without glue or some kind of adhesive, you are essentially "hoping" the coral stays put until it has time to encrust the rock, if it ever does. This works in some cases but usually results in your corals falling from the scape at some point.  The best approach is to use an adhesive of some kind to anchor the coral onto your aquascape. 

Super Glue Gel

Super Glue Gel is the preferred adhesive because it will set up underwater and is fairly easy to work with. When exposed to water, it forms a skin that allows you to sort of mold it like clay, without covering your hands in glue. It's best to apply a dime-size dollop of glue directly onto the coral or coral mount outside of the tank, then dip that into the water where a thin layer of glue will immediately cure to form a protective layer. This then makes it easy to mold into the crevices of the rocks. Hold the frag in place for 60 seconds and most any piece should hold.  


In some scenarios, Epoxy can work just as well but has some limitations. Epoxy cures underwater but takes 24 hours or more to fully cure and tends to create an over-skimming situation with whatever byproducts get into the water during that curing time. It is not tacky and will not "adhere" to wet surfaces but works well to build support around a large frag plug or coral skeleton.  Some hobbyists find a combination of an epoxy foundation with some super glue to hold the coral works great too.  

Tips & Tricks For Success

  • As mentioned above, always secure coral using an adhesive
  • Corals placed on the sandbed can get covered in sand, be mindful of fish and other animals that can cover it.
  • Super Glue forms "skin" as soon as it comes in contact with water. This is great for keeping glue off your fingers but also means it won't immediately adhere to the rock.  
  • Epoxy can cause your skimmer to over-skim and overflow the skimmer cup. Turn off your skimmer when using epoxy. 
  • Don't use a plastic super glue container to eject super glue underwater because it will draw water back into the container and ruin the remaining glue.  Only use the metal containers underwater.


  1. Turn off your protein skimmer.
  2. Turn off your powerheads and the return pump.
  3. Turn your lights down or into acclimation mode.
  4. Clean the rock surfaces to be free of algae using a firm bristle brush before gluing.
  5. Trim or remove frag mounts if possible.
  6. Be sure to test fit the corals into your aquascape to ensure you like what it looks like. 
  7. Attach corals with glue or adhesive. Let the adhesive cure before turning on your pumps and skimmer. 

How To Attach Soft Corals: Soft corals will eventually attach themselves to the rock as they grow. You just need to hold that coral in place long enough for it to attach itself. Wedge the coral in place, gluing it to the rock directly, holding it to the rock with a rubber band, or using the toothpick method are all viable solutions. 

How To Attach Stony Corals: Stony corals are often best adhered with super glue. For larger corals like Euphyllia, you can use Epoxy to create a foundation that will hold the coral, then glue the coral base into that epoxy foundation with super glue. Small sticks of SPS can easily be removed from the coral mount and glued directly to the rock.

How To Attach Encrusting Corals: In this scenario, you typically cannot remove the coral from the mount. Just glue the entire mount onto your rocks and it will eventually grow out and encrust onto the surrounding rock.  

Learn More With BRStv: Week 38: Mounting corals: epoxy, super glue, and lighting tweaks | 52 Weeks of Reefing #BRS160