How can I tell if my fish has ich or Lymphocystis?

[Herndo]

I'm currently cycling my tank with some sailfin mollies and they are happy and doing great and I believe my tank has finally cylcled. But one of the mollies, (who appears pregnant) has 4 or 5 white spots or growths on her tailfin. It's only on here tailfin. I haven't seen any rubbing nor are there any spots on the other fish or on this fishes body. So that leads me to beleive that it is Lymphocystis, which in non contagious and I don't have to worry about adding more fish now that my tank is cycled correct?

I also can not find any pictures on the net to help me differentiate these diseases. Whatever this fish has, came from the LFS, because these are the first fish in the tank. I do have some hermit crabs, but I'm positive that this fish was like this when I get her.

 

[OrionGirl]

If possible, look at the spots from a side shot. Ich cysts look like a grain of salt sitting on the fish, while a tumour will look like a bulge sticking out of the fish. HTH

 

[Herndo]

It deffinately looks like salt

What should I do before I put more fish in? All I have now are those fish, some blue legged hermit crabs and the babies the mollies just had.

Is there anyway the fish could have gotten this from the live rock?

 

[OrionGirl]

You'll need to a) treat the fish, b) leave the tank without fish for quite some time--6 weeks, at least. The life cycle of the marine parasite is similar to the FW ich, in that it infects fish, forms the cyst, which falls off, and later hatches into the free-swimming tomite, that looks for a new host. There is some evidence that the cyst stage can last much longer in marine systems, even with increased heat.

To treat--remove all fish from the tank. In a hospital tank, raise the temp to 86, and treat. There are many effective meds out there, but most will kill live rock and sand, so shouldn't be used on the main tank. If removing them is not an option, Kent ReefRX (think that's what it's called) may be safe, if used properly--search for a post from gbloton, as he recently used it in his tank with good results.

Do not add any fish until you have at least 2 weeks without any sign of the parasite. And, this likely came in on the mollies. The fish were probably exposed at the LFS, and had a subclinical infection, confined to the gills where it's difficult to detect. The stress from the cycle probably lowered their immune system enough for the parasite to take off.