minnow tumors

Question
We have some minnows (1.5 inch) we bought for a community 20 gallon tank.  Two of them seemed to develop tumors--this was months ago--we moved them into a "swamp tank" where a frog and toad live, and they have lived there happily ever since but the tumors seem to slowly increase on them.  They are big pin-head size, whitish and just under the skin.  One has only two tumors, the other has 6-8 including one on the tail fin.  Any thoughts?  I am not the fish expert in the house, just the curious nurse.

Answer
Hi Carol,
I'm sorry to hear about your fish. Tumors are common with fish but I wonder if thats really what your fish have? Maybe they are parasites or a cyst? Could they be ick? This is just a guess but its worth checking into- picture-
http://www.fishchannel.com/images/freshwater-ich-650.jpg

Cysts can be caused by Nodular disease which develop as off-white to yellowish cysts anywhere on their body. Microsporidian and Myxosporidian Parasites are usually responsible. Few studies have been done and the parasites are poorly understood. There really isn't a reliable treatment but it may go away on its own or the fish may have it for the rest of its life. Fortunately it is somewhat rare and remember I'm not saying this is what your minnows are infected with.

Lymphocystis is caused by a viral infection and symptoms are characterised by raspberry or cauliflower like growths on the skin and fins. It often begins as small white cysts which gradually increase in size over weeks or even months.

Fish pox is a viral infection causing white, grey, or pink growths appear on the skin and fins. They can appear as small waxy-like growths or bumps on the skin. It is sometimes confused with Lymphocystis but it has a rougher raspberry like growth to it. Fish pox has no reliable treatment this disease most often affects coldwater aquarium and pond fish, in particular, Koi. There is no reliable treatment. But fortunately it too is somewhat rare.

Tumors are in fact something I have dealt with before in small minnows. But usually the tumors do not show up as white spots. But instead as bumps under the skin and they never show up on the fins themselves. Of course there is no cure and the tumors seems to particularly develop more so with aging fish. The affected fish will live quite happily until the tumor overwhelms their system or they die of old-age. If a fish ever seems to be suffering, its best to put him down. The clove oil method is the best way as its most humane for the fish.

Unfortunately as much as I wish I could, I cannot be for certain what your minnows are affected with. Hopefully they will recover but all you can do is try your best.

Make sure the water is very clean. I'm sure you are already, but with frogs and toads, the water could get dirty very quickly.

Best wishes and I hope this helps!
Karen~