Problem Needs Diagnosing

[BorisTheBlade]

I have Cory Trilineatus in my recently cycled tank. The other day my friend said one had redness around it's pectoral fin. I couldn't really see it as i'm mildly colour blind. Today I come home and it clearly has a small lump in the same place at the top of the pectoral fin where it connects to the body, probably a little bit smaller than it's eye. The other fish are fine, and the fish in question generally seems okay i.e swimming around, digging, being a cory.
The tank was recently cycled, and I did have a problem getting nitrates down from 40-80ppm range before the fish went in. That is now under control and below 10. Ammonia and Nitrite are 0, pH 7.
I'm not sure if it has just been cut by a bit of driftwood for example, or if it is something much more serious. I wish I could get a photo but I don't have a camera at the moment and the fish doesn't sit still long enough anyway.
 
Thanks
 




 

 

[DoubleDutch]

How long is your trili in your tank Boris? Is the substrate / sand totally new as well. I'm not totally sure, but I noticed this "problems" more often in cases Corys were put in a new tank with new substrate / sand.
Could be that the good bacteriacultures are to small so others (or some kind of fungus) irritate / infect the fish. Some people advise to wait for about three months before put Corys fot that reason. In most cases i know the redish color dissapeared in some days without treating. Pristine water / waterchanges / Indian Almond leaves aso will be good !!! As I said I am not totally sure, so keep a close eye on this fellow and if/when it gets worse : meds are needed. Other / different reactions and ideas appriciated.

Greets Aad

 

[BorisTheBlade]

Thanks for the reply.
 
It has been in the tank just over a week. The tank was set up about 2 months ago, and the sand was new when set up. I fishless cycled the tank with ammonia.
 
Unfortunately my LFS didn't mention the corys were unsuitable for a new tank and I must have missed it in my research. I have been doing plenty of water changes and i'll keep them up to ensure water quality.
 
I'm just worried that either the little guy is going to die unless I do something or is contagious.

 

[DoubleDutch]

Not everyone got that idea Boris, but some guys do. It could be true. I didn't wait that long.
As I said I've seen cases alike, often in new started tanks. It appearde not to be contagious in that cases.
Could be an idea to buy some meds (just in case), though I don't know really which ones living in Holland!
Maybe others will react during the day telling you to treat immidiately or what meds you should get.
I'll follow your thread and hope it will be better soon.

Aad