Monday evening I noticed three white spots on the body of our Blue Tang. First guess and fear is Marine Ich so reason to get as much information on it as possible.

Tuesday started searching my regular forums for ways to treat Marine Ich, during this search I found out that Tangs are some of the most vulnerable fish to ich. However, the Blue Tang is a very strong fish and has a high ich survival rate. One of the members from tropischzeeaquarium.nl started a post in which he complaints about the lack of information on how the disease evolves. He also has a Blue Tang that had three spots, sometimes it becomes less and sometimes it’s worse. His Blue Tang eats correctly and looks fine. He feeds Artemia that has been soaking in a bowl of water with garlic pieces. His only notice was that the Blue Tang was a bit jumpy (scared easily).
All this sounds pretty familiar, our Blue Tang also has three spots now (don’t know if they become less or more) but eats normally and looks good. Also our Blue Tang is a bit jumpy and on top of that he is bullied around a lot by other fish. Maybe the treatment used by PGT is something worth trying.
The response to this post by roelsil, a user that seems to know a lot of seawater aquariums and also has a very nice aquarium himself was that he thought there wasn’t much going on. He said the Blue Tang is sensitive to ich, but also resistant to it. He also had a Blue Tang that had ich when they did maintenance on the aquarium because of stress, but after a while it would become less. Only when loads of spots appear there was a reason to worry.

This is somewhat a comfort, but what if you do want to treat against Marine Ich. On tropischzeeaquarium.nl there are many topics about Marine Ich. Two users used a product from Salifert called Stop Parasite. It can be used in an aquarium with corals but I did found a warning to dose carefully. If combined with a month rest and some garlic in the sump it should pass away without “much” damage.
One person left his light on constantly for 3 days and got the Marine Ich out. Downside to this method was that his tank was in chaos and he didn’t safe all his fish.
Another solution, found more often, is UV-c light. When left on 24 hours a day 7 days a week it kills Marine Ich and when combined with Ozon it gives your crystal clear water which makes the effect of the UV-c even better.

And then there was also a discussion topic on tropischzeeaquarium.nl about what people do to fight Marine Ich. From this I concluded that in an early stage garlic works fine, put it in the sump and cut some through the food and give the whole aquarium some rest and it should be gone. The UV light is mostly used to prevent ich more then to cure ich. Also when there are a lot of particles floating in the water the UV light might not be effective enough. Also the Stop Parasite is mentioned once in the discussion, but this was at a point where already fish where very weak, not really proven to be a good solver.
In an advanced stage ich is treated by either catching the fish and putting it in Quarantine, then treat the tank with copper sulphate. Then after the ich is gone slowly get the fish used to normal water again so he can rebuild his slime coat. The copper sulphate damages the slime coat of the fish, so when inserted back in a tank with corals the sting cells of the corals may kill the fish in the end.
Another way that was described is by putting the fish in a sweet water bath for max 10 minutes (more would kill the fish). It seems that the osmosis pressure of sweet water kills ich.

Many solutions and options, but what is ich exactly. Many sites can be found on this and some interesting articles can be read about what it is, what it does and how it lives. Now I can copy entire articles, but if you are really interested I will put the links below. However, in short on what it is and how it evolves.
Ich has four stages in its life cycle, it needs a host to survive and evolve through these four stages. The first phase (maybe not first, but that is a chicken/egg discussion) it is called a theront. Theronts swim around the water searching for a suitable host, if they don’t find one in 12 hours they die. However, when one of them is successful it goes into the feeding stage, known as Trophont. In this stage the parasite feeds on tissue fluids, this is also the moment in which you can see distinctive white spots that form around the parasite. In this stage treatment is useless since the Trophont is to well protected against any treatment. Only when in a free-swimming stage the parasite is vulnerable.
The Trophont will grow till it reaches up to 3 – 5 mm, at this point the Trophont will leave it’s host. It will then attach to any type of substrate and turns into a thick skinned Cyst called Protomont. Inside the Cyst several 100 new Theronts will form that will then spread out to restart the life cycle.

One part I thought I just needed to copy and paste is from reefsanctuary.com and was written by a user called leebca. In here he/she describes Subjective and Non-Subjective Observations, Claims, and Common Myths. Many of these points say that most of the things mentioned on the forum don’t offer a solution, just a relieve.

1. Some Tangs seem more susceptible. True. Their mucous coatings are reduced in thickness and composition. They swim up to 25 miles a day in the ocean in search for food so maybe Mother Nature provided them with this as a means of 'escape.'

2. It goes away on its own. Untrue. Only visible at one stage IF it is on the body or fin of the fish. It’s the life cycle. If it was once seen, then it hasn't gone away -- it's just not visible to the aquarist.

3. It goes away with a ‘reef-safe’ remedy. Untrue. This is one of the biggest and most 'dangerous' of the misrepresentations in the hobby. The aquarist thinks everything is okay when it isn't. What usually has happened is that the parasite has killed the fish it will kill and the rest have developed a resistance or immunity. The parasite is still in the aquarium, possibly infecting the gills of the fish where it can’t be seen.

4. It was gone then when a new fish is added, it is there again. Not true. See 3. It wasn’t gone or the new fish brought in the disease with it. A new addition to an aquarium can be the stress which triggers the other fish to reduce their defense or immunity, thus allow the parasite to 'bloom' to the point where the infection is now visible to the aquarist.

5. The fish lived the last outbreak then died during the second or subsequent outbreak. Can be true. The fish had a resistance or immunity that it lost.

6. It was accurately diagnosed as MI spots, then never showed up again. It wasn’t MI or the fish quickly developed an immediate immunity or resistance, or the fish is still infected in the gills.

7. MI can ‘hang around’ almost unnoticed with just a body spot now and then because it often resides just in the gills. True. So ‘it is gone’ after ‘it was here’ is very unlikely.

8. Aquariums always have MI. Untrue. MI can be kept out of an aquarium. Just quarantine all fish and don’t let non-quarantined livestock get into the aquarium. After keeping thousands of marine fishes, my home aquariums have been free of MI since 1970.

9. Fish always have MI. Untrue. In the wild they often show up to 30% infected (or more) but the wild fish survive minor infections. In the tank the parasite can 'bloom.' In the tank the fish can't get away. The combination of bloom and no escape will overcome the fish. In capture and transportation the fish can share the disease and thus many wild caught marine aquarium fishes do have this parasite, but not all.

10. Like 9. a fish can't be made to be totally rid of MI. Untrue. All marine fish can be cured and rid of any MI infection.

11. Just feed the fish well and/or feed it garlic and it will be okay. Untrue. I compare this approach to this one: "Granny has pneumonia. Let's keep her home rather than take her to the hospital. We'll feed her well with chicken soup and vitamins." Nutrition, foods, vitamins, etc. don't cure an infected fish. An infected fish is sick and is being tortured by the itching and discomfort. It might pull through and obtain Resistance or immunity (see above) but while you sit comfortably in your home, the fish is being stressed by having to contend with a parasite. Don't let this happen to the fish. Cure it!!

12. A new cure has been discovered. Unlikely. If the aquarist thinks they have found a new cure, then have it researched and independently tested. It's easy and cheap. If it is as good as the above 3 then the professional veterinarians, private and public aquariums, fish farms, and I will use it. The aquarist needs to keep the perspective of how devastating this parasite is not to just the hobby but to the whole fish farming industry. Any new way of 100% treatment will make headlines!

13. If the MI can't always be detected, then why bother with a quarantine procedure? In the confines of a small quarantine and being there for no less than 6 weeks, the MI parasite will make itself known because the fish is weakened and the fish can't get away from being re-infected by multiplying MI parasites. In other words, the quarantine procedure instigates a 'bloom' of the parasite which will make it visible to the aquarist.

14. All white nodules fall off the fish and move on to the cyst stage. Untrue. It has been discovered that, on very rare occasions (why we don't know) the white nodule will encyst and rupture while still on the fish.

15. UV and/or Ozone kills MI. Ozone doesn't kill all parasites that pass through the unit, nor does the water treated with ozone kill the parasites. UV only kills the parasites that pass through the unit. Not all MI parasites will pass through the unit, so the UV will not rid an aquarium of MI. A UV can help prevent a 'bloom' of the parasites however, and thus help in its control. UV is not a cure nor a preventative measure for MI.

16. Spots are MI. Untrue. Probably one of the most problematic causes for rumors and myth-information in the hobby is assuming the spot is Marine Ich when it may be one of another few dozen other parasites or conditions (e.g., pimple-like reaction to infection) that look like Marine Ich. The mis-diagnosis is often the cause for claims of what cured MI, when the fish didn't have MI to start with.

17. My LFS quarantines their fishes for 2 weeks and I only buy them to be sure they are healthy and free of MI. Have you been reading the above? The 2 weeks is not long enough. Was the 2 weeks in isolation or is the fish's water mixed with other fish's water? Seeing is not believing, right? LFS employees don't have time to closely observe and study the fishes they have in stock, for a full 6 weeks. The truth is out there. . .Trust no one.

For the full post check http://www.reefsanctuary.com/forums/fish-diseases-treatments/23132-marine-ich-myths-facts.html

Wednesday I checked again, wanting to make some pictures to see if it was Marine Ich or not and guess what…not a single trace left. No visible spots, no heavy breathing, nothing out of the ordinary. The big question now is, was it MI? If it was, is it still there but no longer visible? I did start adding garlic to the fish food, maybe because of this the Blue Tang got more resistant to MI and made the visible part disappear.
I’m going to continue with the garlic and maybe add an Ozone and UV filter. Guess it can’t hurt to do this.

For more information check
http://www.fishchannel.com/fish-health/saltwater-conditions/marine-ich.aspx
http://reefkeeping.com/issues/2003-08/sp/index.php
http://saltaquarium.about.com/od/ichparasiticdiseases/a/aa_cryptocaryon.htm
http://www.reefsanctuary.com/forums/fish-diseases-treatments/52236-curing-fish-marine-ich.html