Prime Coral Stop RTN is a complete coral dip used to treat common coral parasites. It is the only treatment effective against RTN, STN, and Coral Bleaching parasites. It is also effective against acropora eating flatworms, montipora eating nudibranchs, polyclad worms, black bugs, common flatworms, and eggs.

Do NOT add to your saltwater system. Prime Coral STOP RTN is a coral dip.

Use as directed. Not for human use. Does not contain hazardous materials.

Contains natural plant extracts. Use protective wear when handling, eg. gloves and eyewear. If exposed, rinse thoroughly under running water. If rash develops, seek immediate medical attention. Keep away from children.

Caution: Not all infected corals will survive treatment. Use at your own Risk.

Note: SPS corals are more susceptible to heavy infestation.

Makes 4 gallons of coral dip. Use mixed contents within 4 weeks of mixing. Keep refrigerated.


  1. Add contents of small glass bottle labeled “A” to large bottle labeled “B”.
  2. Fill the large bottle with RO water up to the neck (final volume will be 60ml).
  3. Mix contents thoroughly for 15 minutes.
  4. Use 15ml of mixture in bottle “B” to make up 1 gallon of Prime Coral STOP RTN dip in normal salt water (your system salt water) in a separate container.
  5. Place Coral in dip for 5 minutes only. If treating flatworms, nudibranchs, and eggs then use 7 minutes.
  6. Gently rinse coral while in Prime Coral STOP RTN dip.
  7. Take coral out of dip and rinse in fresh saltwater (from your system)
  8. Return coral to your tank to an area of moderate flow.

Prime Coral STOP RTN is effective against microscopic parasites that cause coral RTN, STN, tissue loss, bleaching, polyp melting and retraction. These parasites prey upon all coral containing zooxanthella including LPS, SPS, and soft coral. These RTN parasites cannot be seen without a microscope as their average size is 0.06 millimeter.


Dip all new corals with Prime Coral STOP RTN to help prevent coral disease. Infected corals should be dipped every 2 days until coral health and color returns. Use Prime Coral Prevent RTN in-tank treatment in conjunction with Prime Coral STOP RTN coral dip to eradicate RTN parasites from your system. Successful treatment of ill coral requires both Prime Coral STOP RTN dip and Prime Coral Prevent RTN in-tank treatment.

Keep bottle refrigerated. Mix well before use.

Check out of full treatment protocol.

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