August 4, 2026 Michael Maclean

The Beginner's Guide to Coral Dipping: What, Why, and How

You've just received a beautiful new coral. It's colourful, healthy-looking, and you're excited to get it in the tank. But before it touches your display water, there's one step you should never skip — the coral dip.

Coral dipping is one of the simplest, most effective things you can do to protect your reef. It takes 10–15 minutes and can save you from weeks of pest outbreaks, coral losses, and the heartbreak of watching a healthy tank crash.

Here's everything you need to know.

What Is Coral Dipping?

A coral dip is a short bath in a treatment solution designed to kill or dislodge common coral pests before they enter your display tank. Think of it as quarantine in a cup — a last line of defence between the outside world and your carefully maintained reef ecosystem.

Even corals from reputable suppliers can carry hitchhikers. These pests are often microscopic or well-camouflaged, and a single infected frag can introduce a problem that spreads through your entire tank within weeks.

Why You Should Dip Every Single Coral

No exceptions. Here's what a dip protects against:

Acropora Eating Flatworms (AEFW) — tiny, flesh-coloured flatworms that feed on SPS tissue, leaving white scars and eventually killing the coral
Montipora Eating Nudibranchs — nearly invisible white nudibranchs that devastate Montipora colonies
Zoanthid Eating Spiders (ZESpiders) — small spiders that hide in Zoa polyps and feed on tissue
Coral Eating Flatworms — rust-brown flatworms that smother coral tissue and block light
Bacterial infections — some dips have antimicrobial properties that help prevent tissue necrosis (STN/RTN) from spreading
Algae and detritus — a good dip and rinse removes surface debris that can introduce unwanted nutrients or algae spores

The cost of a bottle of coral dip is trivial compared to losing a prized SPS colony or dealing with a tank-wide flatworm infestation.

What You'll Need

A coral dip solution — purpose-formulated products are far more effective and safer than DIY alternatives
Two clean containers — one for the dip, one for a fresh RODI/saltwater rinse
A turkey baster or pipette — to agitate the water around the coral and dislodge pests
A magnifying glass or loupe — to inspect the coral and dip water for pests
A white container or white plate — pests are much easier to spot against a light background
Gloves — some dip solutions are irritating to skin; always check the label

How to Dip Corals: Step by Step

1. Prepare Your Dip Solution

Mix your dip solution according to the product instructions. Most are diluted in tank water (not RODI) to maintain the correct salinity. Use a clean container — never one that's had soap or chemicals in it.

2. Acclimate First, Dip Second

If your coral has just arrived via shipping, acclimate it to your tank's temperature and salinity before dipping. A stressed coral going straight into a dip can suffer additional tissue damage. Float the bag for 15–20 minutes first.

3. Place the Coral in the Dip

Submerge the coral fully. Most dips require 5–15 minutes — follow the product's recommended time. Don't exceed it; longer isn't better and can stress the coral.

4. Agitate Gently

Use a turkey baster to gently blow water across and around the coral every minute or two. This dislodges pests that are clinging to the tissue or skeleton. You'll often see flatworms, bugs, or debris fall off into the water.

5. Inspect the Dip Water

After the dip, pour the solution over a white surface and examine it carefully under good light. Use a magnifying glass if you have one. Look for:

Tiny white or rust-coloured flatworms
Small bugs or amphipods (most are harmless, but note anything unusual)
Nudibranch eggs (tiny white clusters)

If you find pests, consider a second dip before the coral enters the tank.

6. Rinse Thoroughly

Transfer the coral to your second container filled with clean, temperature-matched saltwater. Gently agitate to rinse off any remaining dip solution. This step is important — residual dip chemicals can irritate coral tissue.

7. Place in the Tank

Your coral is now ready to go in. Place it in a low-flow, medium-light area initially and allow it to settle for a few days before moving it to its permanent position.

Choosing the Right Coral Dip

Not all dips are equal. Here's a quick guide to the main types:

Dip Type	Best For	Notes
Iodine-based (e.g., Lugol's solution)	General pest control, bacterial	Effective but can bleach coral if overdosed
Hydrogen peroxide	Algae, some pests	Use with caution — concentration matters
Commercial coral dips	Broad-spectrum pest control	Easiest to use correctly; purpose-formulated
Coral RX / similar	Flatworms, AEFW, nudibranchs	Industry standard for SPS keepers

Shop Coral Dips & Treatments →

Common Dipping Mistakes to Avoid

Skipping the dip because the coral “looks clean” — most pests are invisible to the naked eye
Using too high a concentration — always follow product instructions; more is not better
Dipping for too long — extended dips stress coral tissue and can cause bleaching
Not rinsing after the dip — residual chemicals irritate tissue and can cause RTN
Dipping in RODI water — always use saltwater at the correct salinity to avoid osmotic shock
Skipping the inspection — the whole point of the dip is to see what comes off; don't skip this step

Do You Need to Quarantine As Well?

Dipping is not a substitute for quarantine — it's a complement to it. A proper quarantine tank (QT) allows you to observe new corals for 4–8 weeks before they enter your display, catching slow-developing pest issues that a dip alone won't resolve.

That said, most hobbyists don't run a dedicated coral QT. If that's you, dipping is your primary defence — so do it properly, every time.

The Bottom Line

Coral dipping is a non-negotiable step in responsible reef-keeping. It takes minutes, costs very little, and protects everything you've built. Make it a habit with every single coral that enters your system — no exceptions.

Your future self (and your SPS colonies) will thank you.