Mystery death of Cory Adolfoi

[G-Lizard]

Recently added two cory Adolfoi to my tank. After four days, I found one of the fish dead when I went to do the morning feed. The other one died after 10 days, again, found at the morning feed. There were no signs of either fish falling ill, and all the other fish in the tank seem healthy. Water tests are fine (no Ammonia present and ph is as it always has been, about 7.6). The other fish are 10 wild green tetras, 1 bulldog Pleco, 6 harlequin Rasboras, 2 Apistogramma agassizii, and 5 Amano shrimps. The only thing I noticed with the dead fish was with the second death, the fish had a few red lines half way down his body. Should I be treating my tank with something like an anti internal bacteria solution if the other fish are all behaving normally. I am currently doing a 20% water change of my 70 litre tank every 10-14 days.

 

[rmiller]

I would definitely up your water changes. You should be keeping your nitrates below 20 ppm. That may mean changing 50% every 5-7 days. What kind of test kit are you using?

 

[G-Lizard]

I've got the API freshwater master test kit. I took a water sample down to my local specialist stockist and they got the same results as I did, so I don't think my results are inaccurate. I've already upped the water changes so thanks for that advice. I'll keep a close eye on the nitrate levels too - thanks.

 

[Catfish Lover]

One issue I see here. You say you added only 2 cories, they need to be in groups of 6 minimum. So not only being stressed from being in new environment, they were also probably stressed from being in only a pair. Cories are also notorious having a harder time adjusting to new tanks. The fish could have already been sick, it happens, hopefully it happens before the return period so you can get your money back.

 

[G-Lizard]

Thanks for the feedback. I took both of them back. The first time I was told that it was odd and even more so that I'd bought some from a batch which were otherwise fine. I was told that I'd get a fish back for free, but should wait a week to make sure that it wasn't anything to do with my tank causing the problem. Of course, when the second one went, and the red marks were seen, my water was to blame. I was told to treat it, but given no other fish appear ill, and after having read some info online, I didn't want to treat without being sure something in the water was to blame. Given your 'stress due to lack of numbers' theory, and some reading I've done over the past 48 hrs or so, I think I may have learnt a lesson on this one... Once I've given the tank another week or so, I may try some different cories and see how they get on...in larger numbers this time!

 

[Catfish Lover]

Thanks for the feedback. I took both of them back. The first time I was told that it was odd and even more so that I'd bought some from a batch which were otherwise fine. I was told that I'd get a fish back for free, but should wait a week to make sure that it wasn't anything to do with my tank causing the problem. Of course, when the second one went, and the red marks were seen, my water was to blame. I was told to treat it, but given no other fish appear ill, and after having read some info online, I didn't want to treat without being sure something in the water was to blame. Given your 'stress due to lack of numbers' theory, and some reading I've done over the past 48 hrs or so, I think I may have learnt a lesson on this one... Once I've given the tank another week or so, I may try some different cories and see how they get on...in larger numbers this time!

I've got 11 peppered cories in my 55. I've only had them for 3 weeks and they are some wimps. Pretty much hide all day in their cave and under the driftwood and come out at night.

 

[Whiteout]

I've got 11 peppered cories in my 55. I've only had them for 3 weeks and they are some wimps. Pretty much hide all day in their cave and under the driftwood and come out at night.

I have 5 emerald cories and 1 panda corie and they will school with my gbr

 

[Catfish Lover]

I have 5 emerald cories and 1 panda corie and they will school with my gbr

You really need to up those pandas

 

[Whiteout]

You really need to up those pandas

Once I can find more I will def up them they are hard to come by in GA