I know of no hyposalinity resistant Marine Ich (Cryptocaryon irritans) though rumors keep coming out of Asia and spread by people who have had apparently no success with the treatment. It is also a favorite of copper medication manufacturers to claim that hyposalinity doesn't work.
I have been able to account for failures due to one or more matters, from a set of common errors or omissions:
1. It isn't the length of time the fish is kept in hyposalinity -- it is the length of time the fish is kept in hyposalinity AFTER the last spot is seen. MANY times the hobbyists has failed to see and note the true date of when the last spot was seen. Some miss seeing the last spot.
2. The hyposalinity was not measured properly and maintained.
3. Quite often when it isn't working it is because the disease isn't Marine Ich. Improper diagnosis is a large error in such situations.
4. The hobbyist has unwittingly contaminated the QT by the tiniest of splashes; using an old net or other piece of infected equipment; introducing infected water for water changes; etc.
5. The hobbyist hasn't used the correct sized QT for the treatment. In this treatment the QT should not be too large compared to the size of the fish.
6. All other things must be kept 'normal.' Such controls are temperature and pH and water quality.
7. The fish isn't being nourished well enough to fully recover. A rare situation, but the fish must be properly nourished to help eradicate the Marine Ich parasite (in some very rare instances).
1 Wouldn't 8 weeks be long enough at 1.008? Even if it took 4 weeks for the last spot to come off the fish (this is a long time isn't it?) then it would still have 4 solid weeks that it would be ich free. I noticed that after about 4 days the fish completely stopped flashing and showed no spots that I could see, but that doesn't mean that they weren't in their gills.
2 I used a refractometer calibrated with pinpoint salinity solution.
3 What other parasite could it be. I noticed in Sep 2007. when I first took the fish out to QT that they would: flash on rocks, had white spots that were about the size of sugar, and the spots would become less about every 5 days or so and then they would come back worse. This is why I thought it was ich and put them into the QT. Is there something else it could be?
4 I was very careful about this in every way. Every time I did a water change I used the same bucket and siphon that were brand new and never got used on any other tank ever. I always washed my hands after putting them in the water of my main DT.
5 I used a 55 gallon tank because I had no other choice. I had to put 18 inches of fish into an uncycled tank the first time, two of which are tangs so they needed some swimming room. I used a simple HOB Aquaclear 110 with foam filters in it for filtration. I had to do daily water changes for a month the first time I tried the hypo to keep it from hurting the fish, and I didn't lose any of them. I thought this may of had something to do with the reason that it didn't work the first time so I decided to try it again. This time the tank had been fully established for quite some time so I only did 2 10% changes a week. I made sure the makeup water was the same temp and salinity that the tank was every time I performed a water change. I always tested the salinity daily and added needed fresh RO to a line that I filled the water to every time I did a change so I had a reference point of evaporation.
6 Temp was always 78-79 degrees and Ph was usually about 8-8.1 and I checked it daily as well. I needed to buffer it a lot, usually I buffered any top off water so that the PH would stay the same at all times. Ammonia 0, Nitrite 0, and even Nitrate never exceed 5 do to all of the water changes that I performed. I kept the tank very clean, I even started to slip with my DT because of all the time I was spending with the QT.
7 I always fed them very well because I knew it was important. I fed 1/2 sheet of Nori every day, and my homemade mush (mystis shrimp, uncooked shrimp, formula 1 & 2, formula brine, formula reef diet, nori, garlic, Selcon, Vitachem, muscles, Cyclopeez, formula 1 pellet, Cuddlefish, and scallops) usually once a day, sometimes two.
I'm very anal about my fish tanks and I take every detail into account when I can to make things better. My big belief is that the fish didn't choose to be here, we brought them here. I would like to make their lives as good as I can and have them live a long time and it's frustrating because I'm not providing that right now. I don't think of fish as money like some, I think of them as another life and more like a family member. I just want to make my fish healthy so that I can add them back into the DT that has been fallow for almost 7 months now so they can be happy again.
What other parasites might I be dealing with here, and would the Cupramine be effective on them? I don't think I can do another hypo treatment with my fish because I just don't think it will work so I will try the Cupramine and see if that works once I get them back up to full salinity (they are at about 1.015 right now).