Per Korndiddy's request in the "Let's talk sticks" thread let's talk a bit about dipping acros. Any discussion about dipping should start with "Why are you dipping?" There are many pests that feed on corals in nature. In the wild there are tons of large colonies and the pests usually are just a nuisance but do little long term damage. In a closed system some of these pests can over populate and become a nightmare. There are likely thousands of potential pests that affect many corals but for the purposes of this thread I will address a couple that commonly affect acropora.
Red Bugs Red bugs are tiny little crustaceans that feed on acropora. The first sign most people notice when their tank is infested with these little critters is a lack of polyp extension. While there could be many reasons for poor polyp extension red bugs are one thing to consider. They (red bugs) can be very difficult to see so if you suspect that you have them examine your acros with a magnifying glass. If you have them you will see tiny little red dots on your corals. Typically red bugs are a severe irritant to your acros but rarely result in death unless left untreated long term. Treatment is performed with the dog de-worming medication Interceptor however that is a subject for another thread.
Acro Eating Flat Worms or AEFW AEFW are as described by the name. Small, flat worms that eat acropora flesh. They can be extremely difficult to see and often times they are only discovered when a coral begins to lose its' flesh. Small "Bite Marks" in your acros flesh is a sure sign that you have AEFW. Failure to act quickly will result in the death of the coral and likely many others in the same tank. In tank treatment for AEFW is currently unavailable although there is some speculation that the flatworm medication for fish called Prazipro may be a solution. While I have used Prazipro to dip acros short term I have never done an in tank treatment with the product therefore I cannot recommend it. Again treatment for AEFW is a subject for another thread.
When acquiring new acros I dip everything that goes in my tank no matter who I got it from and how healthy it looks. Better safe than sorry. People have used many "dips" for acropora with varied success. For the purposes of this thread I will address a few commonly available products.
Iodine Iodine in the form of Lugols or Tropic Marin Pro Coral Cure is commonly used to dip new corals. It can be effective to make AEFW let go and fall off the coral but it takes very strong doses to kill the flatworms and it will not kill the eggs. Great care must be taken to remove any AEFW eggs. Iodine can be useful to reef keepers but it can also be harsh and caution should be observed when Iodine is the dip of choice. Iodine is ineffective against red bugs.
Revive Revive is a "coral wash" produced by Two Little Fishies. It is said to be affective against flatworms and some even say red bugs. I have used Revive for quite a while and it seems to be fairly gentle on the corals being dipped when following the directions on the bottle. Revive will not kill AEFW eggs so one must examine corals closely and remove any eggs that they see.
CoralRX CoralRX is another commercially available coral dip similar to Revive. I have no experience with this product so I will let others comment.
Prazipro Prazipro is a commercially available medication for treating fish that have flatworms. I have used it as a coral dip many times and it seems to be fairly gentle even when mixed in strong doses. Prazipro will kill AEFW but it will not kill their eggs. It is also ineffective in treating red bugs.
I have been using Revive with good results. Thought about buying CoralRx but have only heard from people having experience with Revive, so I went that route.