Coral Fragging 101: Tools, Safety and Healing

Coral Fragging 101: Tools, Safety and Healing

Applies To All corals
Difficulty Read this first
Core Tools Cutters, glue, plugs, dip, gloves
Typical Healing 1–4 weeks depending on coral
Best Time Healthy, established, growing colonies only

Overview

Fragging — cutting a piece of a coral so it grows into a new colony — is how the hobby propagates corals without touching wild reefs. Done right it is low-risk: corals fragment naturally on the reef all the time, and most species heal within weeks. This guide covers the universal toolkit, safety rules, and healing principles; the rest of our fragging series covers the exact method for each coral type, because a mushroom and an Acropora could hardly be more different to cut.

The golden rule: only frag a coral that is healthy, growing, and established in your tank for months. Fragging a stressed coral multiplies the stress, and a struggling colony often dies on both sides of the cut.

What You’ll Need

  • Bone cutters or coral cutters — the workhorse for branching corals
  • Sharp scalpel or razor — for soft corals and mats
  • Frag plugs, discs or rubble — something for the new frag to live on
  • Cyanoacrylate gel glue (reef-safe super glue gel) and/or 2-part epoxy
  • Coral dip (and an iodine-based dip like Lugol’s for fresh cuts)
  • Nitrile gloves and safety glasses — non-negotiable with zoas/palys, smart with everything
  • A small container of tank water to work over, and paper towels you will throw away

Step-by-Step

  1. Prepare everything before you touch the coral: plugs, glue open, dip mixed, workspace lit.
  2. Work fast and keep the coral wet. Most corals tolerate a few minutes of air exposure; none enjoy it.
  3. Make one clean, decisive cut rather than repeated crushing cuts — clean edges heal fastest.
  4. Dip the new frag (and ideally rinse the parent) before anything goes back in the tank.
  5. Dry the attachment point with a quick dab, apply gel glue, press the frag on for 20–30 seconds.
  6. Place the frag in similar light and flow to where the parent lived — not blasting flow, not shade.

Aftercare & Healing

Expect the parent and frag to sulk for a few days — retracted polyps, extra slime. Keep water quality stable and resist the urge to move the frag around; corals heal fastest when left alone. Feeding the tank lightly during the healing window helps LPS and soft corals rebuild tissue. Most soft corals re-attach and open within a week; stony corals typically encrust over their cut edge within two to four weeks.

What Can Go Wrong

Frag detaches: the glue bond failed on wet or slimy tissue — dry the contact point better and use gel, not liquid glue. Tissue recession from the cut: usually water quality or an unhealthy parent; dose iodine dip and stabilize. Brown jelly (LPS): remove the coral, siphon the jelly off outside the tank, iodine dip, return to good flow — and act fast, it spreads. Everything melts: you fragged a stressed coral; wait months longer next time.