unclenedsfishfactory.com

I have three Cory cats (1 Julii and 2 Skunk) along with a bristlenose Pleco and 3 zebra danios in a 10 gallon. I noticed that the barbels on one of the skunk cats are really worn down. From what I've read, this is often the result of infection. I have smooth gravel, so I don't think that's an issue. The fish is acting completely normally. Should I medicate the tank with antibiotics (which ones?) or just wait and see how things go? Thanks.

How large is the gravel? Larger gravel shifts when corys are feeding and can injure the barbels of some species. I try and keep my longer nosed corys in #0 - #2 quartz gravel... thats significantly smaller than what is normally available in the pre-washed estes etc. gravel bags. I had identical problems to you when I started out in the hobby and used large gravels.

You might also be seeing the results of stress from water quality... have you tested ammonia, nitrite, and nitrate? Hows the temperature? Are you doing frequent water changes? Its always easier for fish like corys to go down this road if the water parameters are off.

For treatment, I would keep it simple at the moment. If you find any of the chemistry is off, correct it. Probably do a large water change regardless and keep to a more frequent and regular schedule. Also, its always good to add 2 teaspoons of kosher or aquarium salt per gallon of aquarium water if you don't have any plants. The salt will help keep down infection and may help the cory regrow the damaged parts.

Unfortunately, times when I've seen cory cats develop serious infections around their mouthparts they just haven't been able to come back from it - they are small little creatures and it doesn't take much to overwhelm their little systems. Generally you will see redness, swelling, or fungus if the infection is out of control. If you wanted to add an antibiotic I would try Erythromycin... but salt is a simpler and safer choice if its only the one fish.

Hope some of this helped
-Sam

Thanks for your thorough response, Sam. I'm not sure what size my gravel is according to the numbering system, but it is some pre-washed Estes stuff as you guessed; granule size looks to be maybe 3-5 mm or so. My water temp is 78, pH is 7.4, ammonia and nitrites are at 0 ppm, and nitrates are 20-40 ppm. I do weekly water changes of about 25%. One concern I do have regarding water chemistry is that the water coming out of my tap (in Cambridge) is at least pH 8.4-8.8 at the moment, but my tank water stays at 7.4. I let the new water sit in a bucket for just half an hour or so and I agitate it vigorously with a spoon when I add Tetra Aquasafe (haven't checked the pH after this process). I suppose it would be safer to let the water sit out for a few days. Not sure if the fish are stressed by any pH difference. I'd like to know what the heck is in the tap water that makes the pH so high, but the water seemingly soft.

I just added salt as you recommended; I just have some Java Moss in there. I'll keep a close eye on my fish. Thanks again.

Do you have a sense of how long it might take for cory cat barbels to grow back? My fish is still acting quite normally, but no sign of barbel growth. How long is it safe to keep the 2 tsp per gallon level of salt with cory cats? I've read that they are often not so tolerant of salt, but it's ok "short term" for medicinal purposes. Thanks again.

I suggest the erythromycin

won't hurt
and might help