Corydoras has tumors     4/8/19 To Whom it May Concern: <Hello,> I have a Corydoras that looks like it has multiple tumors. There are more around its topside and one on a fin. Some of the Cory's fins are split, but there are no fungus-like films growing and it is eating and swimming normally. All my other fish seem fine, even my ghost shrimp. I have been trying to take a picture but the Cory is camera shy. :-/ <Understood.> What is going on? <Very difficult to say. Benign tumours crop up in fish for a variety of reasons, including exposure to toxic chemicals (particularly in the substrate) and certain viruses (notoriously, Lymphocystis). Benign tumours are impossible to treat, but the viral ones in particular sometimes clear up by themselves, though this can take months/years. Provided such tumours aren't obstructing important tissues or organs, they aren't life-threatening. Malign tumours do occur in fish, for a varied reasons as they do in humans, and again, aren't really treatable. A few diseases might be mistaken for tumours, such as Fish or Carp Pox, Gas Bubble Disease (usually caused by over-saturating the water with oxygen), and Dropsy. So it's worth researching these and comparing them with your fish.> What do I do? <The short answer is a to judge quality of life while providing the best possible living conditions. If the fish is not distressed, tumours are unlikely to spread, so such fish can be left alone in the fish tank. A varied (vitamin-rich!) diet, clean substrate, and good water quality can help promote recovery. If the fish is distressed, then euthanising the fish may be the best thing to do. Removal of tumours isn't really practical for small fish, thought it can be done by vets under some circumstances, and may be an option with large and valuable fish, such as Koi.> Thanks for all your help! Kris <Most welcome, Neale.> Re: Corydoras has tumors     4/8/19 Thanks for your help! I got a picture, finally. I don’t know if this changes anything about your prognosis. Sorry, the picture is a bit out of focus. <Indeed; not entirely sure what I'm meant to see. Do you mean the swelling between the eye and the dorsal fin? Where the black and white spotted skin seems to bulge outwards? Definitely that looks like a subdermal tumour of some sort. Could be benign, could be malign, but impossible to say. Unlikely to be contagious though, so no real problem leaving this catfish in with the others.> Have a great Sunday! <Alas, 'tis Monday already.> Kris <Cheers, Neale.>

Cory Color, Illness - 05/07/2006 Hello, <<Hello, Judy. Tom here.>> A question that I haven't seen posed...my Schwartzi Cory has a white area above the barbels...only white, not inflamed, but it doesn't seem to be going away...or getting worse. <<Might be genetic, Judy.>> The LFS had me dose a little with Methylene blue, but other than that have left it alone. <<Not a "bad" call on the part of the LFS but, as you're aware, Methylene Blue can/will play havoc with your beneficial bacteria and plants. Generally, it's best not to treat until something specific has been identified.>> His activity is fine-appetite good, also. He's in a 20-gal with testing coming out at 7.0-0-0-5.0 Any ideas or feedback would be greatly appreciated. <<There's certainly no problem with your readings and given that his appetite/behavior is good, I don't see reason for concern here. In my experience with Corys, coloration changes concurrent with a "problem" affect the entire body of the fish. Typically, the fish becomes more "pale" with diminished coloration overall. They also become almost completely inactive and stop feeding, which doesn't seem to be indicated in your case.>> (I'm wondering if it has anything to do with vacuuming with the water changes....am I not doing a good job?. the gravel is natural and not large.) <<As long as you vacuum deeply - all the way to the bottom - when cleaning your gravel, you're doing a good job. Also, a substrate that would be inappropriate for foragers like Corys would be expected to affect the barbels, not necessarily the coloration of the snout.>> Thanks a Lot, Judy <<You're welcome, Judy. Tom>>

Cory constantly moves, and has missing chunk 11/17/06 Dear Expert, I am so thankful to be able to have someone to ask about my poor fish. I have a 12 gal. tank with a couple of Corydoras agassizii, a male Betta, and 4 male guppies. The temp is kept at 78-80 F, water parameters are normal, pH 6.8 to 7.0, negligible ammonia, nitrates, nitrites, etc. and I do a 3 gal. water change with aged water every week. <So far, so good> All fish appear healthy and are eating well except one Cory. I first noticed 3 days ago that he was in constant motion - not swimming, but staying in place and just shimmying. <Strange> At first, I thought he was looking for food, as the motion was similar, but he never stops. His fellow Cory just sits on the bottom, then will look for food, and stop again. I also noticed a pale spot at the front of the dorsal fin, almost as if bleach had been dropped on the Cory's back. Now, there is a chunk if flesh missing from the Cory's back. <Mmm, there is nothing in the tank that would "bite" a piece out... Is there a piece of gear... a pump or such that might do this?> I can't find any similar reference to the movement as it's not jerky, frantic, or flashing. I don't want to use salt, <I would not> as I've read that Corys are sensitive to salt. Do you have any idea as to what his problem might be, and what I can use to heal him? Thank you for your advice. <This could be some sort of "time bomb", nervous/genetic disorder in the one fish... I am torn between urging you not to "treat" with anything for fear of disrupting biological filtration, hurting water quality... and suggesting something innocuous... Bob Fenner>
Re: Cory constantly moves, and has missing chunk 11/17/06 Thank you, Bob, for the response. I couldn't find anything mechanical, and the missing chunk kept getting bigger. The Cory died, so fortunately, I don't have to treat and mess up the stability of my tank. I'll watch to see if other fish are effected, but so far, the rest are doing great. I agree with you that the problem is more than likely specific just to the one Cory. Thank you again for taking the time to answer my question. <Thank you for this update. Life to you my friend. Bob Fenner>