Learn how to mount new frags in your aquarium!

Why mount coral frags?

Often when you purchase coral frags from your local fish store, they will come on plugs or rocks which can be easily knocked over in the home aquarium. By mounting the frags securely you can keep your corals safe from being knocked over into each other or into the sand.

There are many different types of corals and their various physical characteristics will determine how you should mount them. This article is divided into sections depending on what type of coral you're trying to mount.

Epoxy Putty

Whether you are working with hard corals or soft corals, epoxy putty is the ideal tool for mounting plugs and rocks to your main rock-work. Epoxy putty is sold in local fish stores in a long tube of two chemical mixes. As you mix the two chemicals by kneading a portion of the putty together it slowly begins to harden. It is often very foul smelling but corals are apparently unaffected by the nasty smell. Although you can buy it at your local fish store, it can also be purchased at hardwares stores. It is the very same putty as used for fixing boat holes and plumbing leaks. The putty at the local fish store might have the advantage of being purple to match the coralline on your rocks. Not all putties are created equal, Aquascape brand putty does not smell as foul as others, but often makes the water appear cloudy if rubbed underwater. The generic brands of epoxy putty do not usually cloud the water but smell strongly of sulfur.

It is very common to have your skimmer either stop working or go on "over drive" and skim excessively when you introduce putty. This effect will usually go away with in a few hours and as long as your skimmer does not create a flood there is nothing to be concerned about.

Super glue

Super glue is perfectly safe to use in the aquarium, but you should be careful not to get it on your corals as it can cover them potentially causing local tissue damage (particular in hard corals). There are specially sold bottles of super glue for coral frags, but other than variances in viscosity they are all cyanoacrylate the average super glue you can find at the convenience store. You can use the standard super glue when working out of water while mounting corals to plugs, rocks or epoxy, but it does not work well under water. Super glue gel however, can be used underwater. In order to use super glue gel underwater you can squirt a small pile onto the rock where you would like your coral to go. You can then squish the coral plug or coral into the gel until it gets a good hold. You will want to steady the coral for a few minutes underwater while the gel hardens.

Working with SPS corals

Small Polyped Stony corals are usually one of the easiest corals to mount to your rock-work, but they can be delicate so you must be careful when working with them not to break the branches of the coral. Often they are mounted onto porcelain or plastic "plugs" which are specially designed to fit into the plastic light diffusers often used by hobbyist for grow out tanks. The plugs work great for keeping the coral fragments steady in the square holes of the light diffuser, but are terrible when it comes time to mount them onto your rocks.

Depending on your personal preference and where you plan on placing your new coral frag, you may want to approach mounting the coral in a few ways. If your corals is not very well encrusted onto the plug, you may be able to remove it from it entirely. This allows you to mount the coral without having the ugly plug visible in the tank. If the coral fragment had been growing on the plug for a while it likely is well encrusted though, and this isn't an easy option without damaging the coral fragment. In these cases if it often best to mount the plug to your rock-work instead of the coral directly. If you're lucky enough to have a 1/2" hole in your rock-work you can often slip the plug right into it just use a small amount of epoxy putty to keep it secure. Otherwise you might have to use coral cutters to cut the longer protruding portion of the plug away from the main disk where the coral is mounted. This way you can attach the remaining disk flush onto your rock using epoxy putty.

Frag Plugs

Coral fragment plugs are made of a variety of materials and aptly named plugs because of their look. Plugs offer a substrate to attach your coral frags to in an almost universal size that will fit into the plastic grids used to housing fragments at your local fish store.

Although frag plugs are great for growing corals out in frag tanks, they are not very easy to use in the home aquarium. The plug itself is often to big to fit in any holes on the live rock and raised the coral up past the rock when glued down, creating an unnatural look. In order to overcome this problem, you can use coral cutters to snap the plug off, or as mentioned previously remove the coral from the plug depending on type and how well encrusted it is.

Frag plugs can come in a variety of materials though. Oceans, Reefs and Aquariums (ORA), an aqua-culturing facility in Florida uses it's own plastic plugs for many of it's SPS corals. While their plugs fit snugly into the light diffuser racks, they can be very difficult to mount the coral in the home aquarium. Most other outfits typically use cement or ceramic plugs. These have the advantage of looking like rock and the rough porousness of the material provides a good surface for adhesives and coral growth. Ceramic and cement plugs can also be easily broken off from the coral or top disk.