What gave my fish ich? New fish showing no signs or store bought frozen brine shrimp?

I have ich in my tank and there are 2 possible carriers, a new fish or some frozen brine shrimp I purchased. The new fish has not shown any ich symptoms but another fish has the dots all over. Im wondering if he could have already had it and carried the parasites to my tank?The tank was at a constant 77-79 degrees.Already treating for the ich. Just curious where it came from.

your fish can get ich without adding new fish or outside food, especially in the winter when the temperatures are colder, stress and temperature are a huge thing to watch out for to avoid ichhttp://www.peteducation.com/article.cfm?c=16+2160&aid=2421highlights from the above article=Why fish get ich Ich is so widespread that many experts feel that it is present in the environment of most aquariums, especially in larger holding tanks, rearing ponds of breeders, collectors, and wholesalers. In fact, just about every aquarium fish will come into contact with this protozoan at several times in its life. Because it is so widespread, most fish have developed a good immune response against the disease to allow them to fight off the protozoan infection before it ever causes any symptoms. Captive fish that develop ich usually get the disease when their immune systems are not functioning as well as they should be because of stress. We know that stress lowers the immune response and when fish are stressed that is when ich is most prevalent.from the internet=There are many causes of stress in a fish's life, many of which can be made worse or better by the owner. Water temperature, water quality, tank inhabitants, improper diet, and a variety of other factors all contribute to stress, but one of the most severe causes of stress occurs during shipping and handling of a new fish. Whether coming from the wild or farm-raised, the handling and shipping of the fish from their origin to a wholesaler, then to a retailer, and finally to your home is extremely stressful. With the widespread prevalence of ich, it is no wonder that many newly purchased fish are affected.

Get some Rid-Ich and treat the water. It could be from the shrimp, but most commonly, ich is carried from one fish to another. It has a lot to do with keeping their water temperature regulated, also.

A fish can carry the Ich parasite with no visible signs. The Ich can infect the fish's gills where you cant see it, and it only takes one cyst to infect the tank. When you see the spots the tank is already badly infected. That is more likley than frozen food becauseA: the brine shrimp are bred in salt water where there are no fish, so there wont be any white spot parasite in the salty pond.B: Freezing will kill the parasite anyway.Also make sure that it really is Ich, not some random spotty infection from bacteria or fungus that is just attacking a weakened fish.Ian