I doubt it is ich. A bad case of ich is easy to see. The nature of ich is such that the longer it is not eliminated in a tank, the worse it gets. Let me quote you on this from one of the oldest fish sites in the USA:
Symptoms: Fish look like they have little white salt grains on them and may scratch against objects in the tank.
White spot disease (Ichthyopthirius multifiliis) is caused by a protozoan with a life cycle that includes a free-living stage. Ich grows on a fish --> it falls off and attaches to gravel or tank glass --> it reproduces to MANY parasites --> these swarmers then attach to other fish. If the swarmers do not find a fish host, they die in about 3 days (depending on the water temperature).
Therefore, to treat it, medicine must be added to the display tank to kill free-living parasites. If fish are removed to quarantine, parasites living in the tank will escape the treatment -- unless ALL fish are removed for about a week in freshwater or three weeks in saltwater systems. In a reef tank, where invertebrates are sensitive to ich medications, removing the fish is the only option. Some people think that ich is probably dormant in most tanks. It is most often triggered by temperature fluctuations.
Remedy: For most fish, use a medication with formalin and malachite green. These are the active ingredients in many ich medications at fish shops. Some products are Kordon's Rid Ich and Aquarium Products' Quick Cure. Just read the label and you may find others. Check for temperature fluctuations in the tank and fix them to avoid recurrences. Note that tetras can be a little sensitive to malachite green, so use it at half the dose.
Use these products as directed (usually a daily dose) until all of the fish are spot-free. Then dose every three days for a total of four more doses. This will kill any free-swimming parasites as they hatch out of cysts.
Another remedy is to raise the tank temperature to about 90 deg F and add 1 tsp/gallon salt to the water. Not all fish tolerate this.
Finally, one can treat ich with a ``transfer method.'' Fish are moved daily into a different tank with clean, conditioned, warmed water. Parasites that came off of the fish are left behind in the tank. After moving the fish daily for a week, the fish (presumably cured) can be put back into the main tank. The disadvantage of this method is that it stresses both fish and fishkeeper.
I have highlighted the important part in blue. The point is that if one does not kill off ich, its gets worse and worse and it will eventually kill fish. You can see pictures here http://badmanstropicalfish.com/fish_palace/tropicalfish_disease_identification.html#Ich
click on each of the 4 pictures to enlarge them and you will see what ich covered fish look like.
Finally, there are some strains of ich that have a resistance to many of the more popular cures. One thing that has been shown to work in such cases is Quinine Sulfate although it is generally not the preferred medication. You can Google "Quinine Sulfate + Ich" vor more information. This is the same drug used to treat malaria in humans. Malaria is a protozoan disease as is Ich.
Hope this helps