Ich Outbreak

Could you load up the QT w/ meds (methylene blue or malachite green both kill ich) & cycle the fish through it, 1 or 2 at a time for a few hours ea.?? This approach would allow you to maintain same pH, sg etc. as main tank, which would minimize the stress on the fish, just give them ea. a dip in a few cups of main tank water on the way back so you don't transfer dye back.

AFAIK - Ich is pretty much always there, it just doesn't show up on fish unless/until they're stressed (bagged, moved etc.).

To properly do a hyposalinity treatment you have to do that for a full 30 days with your fish. The lifecycle of the ich parasite is 30 days. If your DT has ich it will be in the substrate so any fish you put in there will eventually end up with it. Especially if they are stressed. Tangs, especially the hippo and the powders are ich magnets. Check out this reference article about marine ich and hypo treatments.hyposalinity reference

Sorry to disagree here, but Ich is NOT always in a tank and must be brought to a tank through a host. It is true that fish will get Ich faster, or in more intensity, when stressed or otherwise weak, but having a tank with a stressed fish does not result in Ich, nor does tank temp result in Ich.

Ich is a protozoa and so it has to be introduced into an environment. Saltwater Ich is also NOT the same as Freshwater Ich and is COMPLETELY DIFFERENT.

Freshwater Ich gets its name from its scientific name: Ichthyophthirius

Saltwater Ich's scientific name is: Cryptocaryon irritans and gets its common name because it resembles freshwater Ich in appearance and symptoms, but can actually remain in the 'little white spots' form for much longer than FW Ich.

Socutemolly,

I really am sorry to hear about your current situation. I am NOT the expert here by any means as far as saltwater fish or tanks in general and have just started out with my own tank. However, I am a bit of a research 'nut' and like to read about this hobby and so I hope I can offer some advice that I have read which you can use.

The first thing I would say is that you might want to quaranteen for a bit longer in the future to be sure that your new fish are going to be healthy. Like I said before, Ich is not something that is natuarally occuring in a fish tank, it has to be brought into the tank from another tank.

This doesnt really solve your problem though right now and I agree that you should have started out with the more natural type treatment of hyposalinity. From what I have read, this treatment should be done for at least three weeks, regardless if the fish lose the appearance of having Ich. I guess the good thing about SW Ich is that it cannot survive for long in low salinities or in freshwater so by continuing treatment for three weeks, you are theoretically able to remove all of the Ich from your tank. The biggest warning that I most commonly have read about when treating with hyposalinity is to slowly acclimate the fish and tank itself back to normal salinities and try not to shock the fish by going too fast.

Again, not really wanting to start a disagreement here, but Malachite Green or other common Freshwater Ich treatments will not work on saltwater Ich. Malachite green is actually the die itself that is found in the medicine and is sometimes used to to dye other products we buy like clothes. So, in other words, if it did work on saltwater Ich, you would want the dye to remain on the fish but in this case, it might make your fish appear that they are cured, but they are not.

The only other treatment that I have read about is the use of copper salts for getting the Ich done and out of your life. Of course, we all know that copper is just a bad bad thing for display tanks, but it might save you time and money to get yourself set up somehow with a q-tank that you never plan to use for inverts and treat with copper. It might also be good to do this coupled with the hyposalinity in your display tank so you can be somewhat sure that the Ich will not reoccur.

There are other things you can do as well to help protect yourself in the future. A UV sterilizer is commonly heard of being used to protect against Ich but the warning about them that was given to me be a marine biologist student and very avid reef keeper was that they are not infallable. Of course, a lot of water can be directed around most UV sterilizers, especially if using a sump or refugium. The key would be to use one that is rated for much more water than your tank holds to increase the chances that it is getting most if not all of the water treated quickly throughout the day.

I also agree with many people's advice about introducing 'cleaner fish/shrimp' into a tank to help with parasites, however I know that again, this is not going to protect you 100% against Ich. To give you a hard lesson learned from my tank, I had ordered three Neon Gobies to help clean my fish. When the first one came to the store (they were staggered due to availability) and I picked it up, I was amazed at how small it actually was! While I couldnt really take it back to the store (they were closed, my wife had picked it up and had it floating in the tank when I got home), I couldnt really put it in my tank since it would get sucked throught the various intakes and powerheads in my tank. Unfortunatly, it didnt make it over night in the small breeding net that was my only real way of keeping it safe. Point is, they are teeny! Here is a pic (it is big, so I will just give the link):
http://i96.photobucket.com/albums/l162/tommygunnz76/Saltwater Tank/FingervsGoby.jpg

Lastly, I just wante dto state that from everything I have ever heard about saltwater fish, hippo tangs (regal tang) are almost the easiest fish available to catch Ich. I have actually been denied the sale of one since I didn't have a UV sterilizer on my tank and this fish could have been the source of your outbreak as it apparently is for quite a few others. (I am making that assumption without knowing the whole story and basically just trying to make a point)

Links to my sources of information:

http://en.wikipedia.org/wiki/Cryptocaryon

http://en.wikipedia.org/wiki/Cryptocaryon (Read about half way down the page under the subheading "Chromatic Form of Malachite Green")