Two corydoras missing barbels--ideas to help them?

I was just saddened to notice that two of my corydoras are missing all of their barbels. I have 9 Sterbai corydoras, two bronze, and one panda. Their 40-gallon tank has been established about a year. I also have a pleco, four tetras, and 9 rasboras in the tank. All of the other fish seem to be doing ok and the other corydoras seem healthy/growing well.

A week ago I noticed a spike in nitrates up to 80--usually the nitrates stay around 20-40 in my tank. We also had the heat go out for two days a couple of weeks earlier (even with two thermometers still working, the air around the tank was 55 degrees) so there was likely some water temp fluctuation.

I did a 25% WC last weekend and about 15% WC again today, and the nitrates are down to 40 and the ph is 7.4. 0 ammonia. I use prime in the water and occasionally add stability as well with water changes.

Has anyone had success in having barbel-less corys survive or any suggestions on how I could help them? I feed them a variety of food so there is usually plenty around (bug bites flakes for the top feeders, top fin algae thins and Api pellets for the bottom feeders. Would adding stress fix to the water help? if so, how much?

I would appreciate any suggestions on how to help give the barbel-less corys a shot at surviving.... I really enjoy the corys and want them to thrive in my tank.

 

These are C.trilineatus.

I suspect the substrate to be the issue and cause of the nitratespike as well.

 

It kinda looks like some sort of fungus is where the barbels should be... I don't have any experience with Corys so I wouldn't know. I hope you find the answer your looking for!

 

It kinda looks like some sort of fungus is where the barbels should be... I don't have any experience with Corys so I wouldn't know. I hope you find the answer your looking for!

It is fungus on damaged barbells.

 

I Would change the gravel to fine sand or smooth natural gravel or river stones. But until the cories start to heal, you would be best with no substrate. You may need to treat them in a separate tank.

 

I Would change the gravel to fine sand or smooth natural gravel or river stones. But until the cories start to heal, you would be best with no substrate. You may need to treat them in a separate tank.

A thin layer of sand is better than without any. I doubt these fish will recover. Clean water, anti fungus med and fingers crossed.

 

Thanks for the helpful information, including the correction of the type of corydoras.

I am going to try to set up the two in a quarantine tank with sand bottom and treat them for fungus, although it seems like I should be prepared for them to not make it given the responses...

I had a variety of tetras in my first 20 gallon tank with gravel, and did not know about the sand/gravel issues with corydoras. I am looking into how to switch substrate and planning to try a switch to sand this weekend. I am going to try to find the Caribsea super naturals crystal river sand to use and hoping and I can pull of making the switch so my other fish have a happier existence without the gravel injuries. It seems like my pleco would also benefit from a sand bottom as well.

 

I thought I'd send an update--thanks again for all of the feedback. My two injured corydoras sadly could not recover with treatment.
I have since changed the substrate in my tank to sand after learning about how harmful gravel is to the corydoras. The rest of my fish look much happier now and are adjusting well to the new set up.

 

Sorry about your fish! Are you using plastic plants? I would take any plastic plants ou too!