How to Frag Coral
(Step-by-Step Guide)

Fragging coral is a common method reef keepers use to propagate and share corals between aquariums. In this guide, we show the basic process of safely cutting and preparing coral frags from a larger colony. The steps apply to many common reef corals, including both LPS and SPS varieties. Whether you're fragging to grow your collection or share corals with others, this guide explains the core techniques used by reef hobbyists.

Tools & Supplies You'll Need

Before fragging coral, it’s important to prepare the right tools. Having everything ready makes the process faster, cleaner, and safer for the coral.

Protective Glasses

Protective Glasses

Coral fragments can snap during cutting, so eye protection is recommended.

Frag Plugs or Frag Discs

Frag Plugs or Frag Discs

Small bases where the coral frag will be mounted so it can grow securely.

Coral Glue or Gel Super Glue

Coral Glue or Gel Super Glue

Used to attach the frag to the plug or disc.

Container with Tank Water

Container with Tank Water

Keeps the coral submerged during handling and helps reduce stress.

Paper Towels or Cloth

Paper Towels or Cloth

Useful for drying frag plugs before applying glue.

Coral Dip (Optional)

Coral Dip (Optional)

Helps reduce pests or bacteria before placing the frag back into the tank.

Start With a Healthy Coral

The first step to fragging coral is starting with a healthy, well-established colony. If you're looking for colorful, aquarium-grown corals to grow and frag over time, explore our collection of reef-ready corals available in our store.

Browse Coral Colonies

A Complete 10-Step Guide To Coral Fragging

Fragging coral may look intimidating at first, but the process is straightforward when broken down into clear steps. Below is a simple guide that walks through how reef hobbyists typically cut, mount, and prepare coral frags so they can heal and grow into new colonies.

STEP 1

Choose a healthy coral to frag

Start with a coral that is already well established, healthy, and actively growing. Avoid fragging corals that are freshly added, recently stressed, receding, damaged, or unstable, because fragging adds more stress and lowers the chance of a clean recovery. The best candidates are colonies with strong color, full tissue, and clearly developed growth points or branches.


STEP 2

Remove the coral and keep it wet while handling

Take the coral out carefully and place it in a shallow container or tray with tank water while you inspect it and plan your cuts. You do not want to handle the colony roughly or leave it exposed longer than necessary. Keeping the coral in tank water during prep helps reduce stress and gives you a stable, controlled surface to work with.


STEP 3

Inspect the colony and plan the cut lines

Before cutting anything, look at the shape of the coral and decide where each frag will come from. The goal is not just to create pieces, but to create viable pieces with enough skeleton or base material to heal and regrow. Different corals need different fragging approaches, so you should cut with intention rather than randomly snapping the colony apart.


STEP 4

Make clean, deliberate cuts

Note: Always wear protective gloves and eye protection when fragging corals. When cutting through a coral skeleton, small fragments can snap or jump unexpectedly, which can cause injury or irritation. Proper protection helps keep the fragging process safe and controlled.

Once your cut points are planned, make the cut as cleanly as possible. Do not rush, twist, or crush through the coral if resistance builds; that can tear tissue and damage areas you wanted to preserve. A cleaner cut generally means less collateral damage around the wound and a better chance of recovery for both the new frag and the remaining mother colony. This clean, controlled approach is exactly why saws are often preferred for thick skeletons or high-value pieces.


STEP 5

Rinse the Frag in Tank Water

After making the cut, place the frag into the container of aquarium water and gently rinse it. This helps remove loose skeleton dust, slime, and debris created during the cutting process. Rinsing the frag also reduces the chance of particles irritating the coral tissue before mounting it on a frag plug.


STEP 6

Separate the frag and check for damage

After cutting, inspect both the new frag and the mother colony. You want to make sure the frag has enough structure to mount securely and that there is no major tissue tearing, crushed edges, or loose flesh hanging from the cut. If a piece looks too damaged or too small to survive well, it is better to correct it immediately than glue a weak frag and hope for the best.


STEP 7

Prepare the frag plug or disc

Before gluing, get the frag plug, disc, or small rock ready. Drying the spot where glue will be applied helps create a stronger bond, which is why many reefers briefly pat the frag base and plug dry before mounting. The goal here is to create a stable base so the frag does not topple over, detach, or get blown around once it goes back into the system.


STEP 8

Glue the frag in place

Note: Only use reef-safe coral glue or cyanoacrylate gel when mounting coral frags. Some household or industrial glues can release chemicals that are harmful to corals, fish, and other reef inhabitants. Using reef-safe products helps protect your aquarium and ensures the frag can heal properly.

Mount the frag using cyanoacrylate gel coral glue, which is commonly used because it cures underwater and adheres well to both coral and mounting surfaces. Add enough glue to create a firm hold, then press the frag into position so it sits naturally and securely. You do not want the frag leaning awkwardly or balanced on a tiny point, because instability during the healing phase can slow recovery.


STEP 9

Return the frag to a stable recovery area

After mounting, place the frag in a stable, lower-stress area to recover. The key during recovery is consistency: stable water parameters, appropriate lighting, and enough flow to keep debris from settling without blasting the fresh cut. Newly cut corals need time to heal, and excessive stress right after fragging can set them back.


STEP 10

Monitor both the new frag and the mother colony

Over the following days and weeks, watch for normal healing and polyp extension, but also keep an eye out for recession, excess slime, detachment, or other signs of stress. You are not only checking whether the frag survived, but also making sure the mother colony is healing well at the cut site. Successful fragging means both pieces remain stable and continue growing after the process.


Watch the Full Video Tutorial

Prefer seeing the process in action? You can also watch a step-by-step coral fragging tutorial created by our owner, Nick from Corals Depot. In the video, Nick walks through the same process used in this guide and demonstrates how to safely cut, handle, and mount coral frags.

If you're new to fragging, the video is a great way to see the techniques up close before trying it yourself.

Coral Frag Aftercare

Once your coral frag is mounted, the recovery period begins. Proper aftercare helps the coral heal its cut tissue, attach firmly to the frag plug, and begin growing again. Follow these key recovery practices to give your frag the best chance to thrive.

What Your Frag Needs During Recovery

You can structure this as interactive icons or hover cards on the landing page.

Gentle Water Flow

Gentle Water Flow

Provide indirect flow that keeps water moving around the frag without blasting it. This helps remove mucus and debris from the cut area.

Moderate Lighting

Moderate Lighting

Avoid placing fresh frags directly under intense lighting. Start them in a slightly lower light area and gradually move them to their final placement.

Stable Water Parameters

Stable Water Parameters

Healing corals respond best to stability. Keep temperature, salinity, alkalinity, calcium, and magnesium within normal reef ranges and avoid sudden changes.

Regular Monitoring

Regular Monitoring

Check the frag daily during the first week. Healthy frags typically maintain color and begin showing normal polyp extension after the initial stress period.

Time to Heal

Time to Heal

Avoid moving or re-fragging the coral too soon. Most frags need several days to weeks to fully attach and start new growth.

Typical Frag Healing Timeline

Why Fragging Is Beneficial for a Reef Tank

Coral fragging isn't just about creating new pieces to share or trade — it can also benefit the health and balance of your reef aquarium. By carefully propagating corals from established colonies, reef keepers can manage coral growth, maintain tank stability, and expand their coral collection in a sustainable way.

Key benefits of coral fragging include:

Promotes Healthy Coral Growth

Fragging can stimulate new growth as the coral heals and begins developing fresh tissue around the cut area.

Prevents Corals From Overgrowing the Tank

Many corals grow quickly and can crowd neighboring colonies. Fragging helps control size and spacing within the aquarium.

Allows You to Propagate Your Favorite Corals

A single coral colony can produce multiple frags, allowing you to grow more of the corals you enjoy most.

Great for Trading With Other Reef Keepers

Fragging allows hobbyists to trade corals and introduce new varieties into their reef tanks without purchasing entirely new colonies.

Supports Sustainable Reef Keeping

Aquarium-grown coral frags help reduce demand for wild-collected corals, supporting more sustainable reef aquarium practices.

Common Questions When Fragging a Coral

Still Have Questions?
A coral is usually ready to be fragged when it is healthy, well-established, and actively growing. Look for strong coloration, full tissue coverage, and visible growth points or branches. Avoid fragging newly added or stressed corals.
The most common tools used by reef hobbyists are bone cutters, coral fragging pliers, and diamond blade coral saws. The best tool depends on the coral type and the thickness of its skeleton.
When done correctly, fragging is generally safe and many corals recover quickly. However, improper cuts, unstable water conditions, or handling unhealthy corals can lead to stress or tissue damage.
Most coral frags begin healing within a few days, but full recovery and visible growth may take several weeks depending on the coral species and tank conditions.
Some reef keepers use a coral dip to help reduce pests or bacteria, especially when introducing frags to a new tank. However, it is not always required if the coral comes from your own healthy system.
Freshly cut frags should be placed in an area with moderate lighting and gentle water flow. Once the frag begins healing and showing polyp extension, it can be gradually moved to its final placement.
Use reef-safe cyanoacrylate gel coral glue or specialized coral mounting products. Avoid household glues that may contain chemicals harmful to reef aquariums.
Yes, many corals can be fragged multiple times as they grow. However, it’s important to allow the coral enough time to fully recover between fragging sessions.
Fragging allows reef keepers to propagate corals, manage colony growth, trade with other hobbyists, and maintain a balanced reef aquarium while supporting sustainable coral propagation.