Sick corys, nothing helps

[Corycory]

No one?

[PseudaSmart]

The boards always slow down in summer. Over here the weather has been quite nice.

I will be honest and say that I scanned thru this thread. It seems odd that it is on the back of the fin not the front. On the front usually results from hitting or rubbing.

My first suggestion would be to take a scraping from the affected area and put it under a microscope. You could be surprised at what you see. Recent issues of my own required me to dig deeper. I am still learning myself.

The only other suggestion which really does not solve the problem is to put those affected into another tank and see if it is always the same ones. Perhaps most are immune to the issue.

Jim

[CoryfanAad]

Going back to the first post : are you using JBL Sansibar black sand?

[JamesFish]

If its the small white bump at the base of the top fin on the cory towards its back it should go away with some little help. If you add some alder cones and raise the temp a little it should go away. I dont know exactly what it is but it doesnt to my knowledge harm the fish.

[Corycory]

Thanks so much for the suggestions guys.

The microscope is a good idea but I'd have to see about it though as currently its not an option, plus catching a cory in a planted 5f tank

Going back to the first post : are you using JBL Sansibar black sand?

Not anymore. It was that sand that triggered whatever they had. Then I moved all the corys out of that tank to the 5f tank they've been in for over a year. The substrate now is soil capped with a different brand sand but it's a coarse type of sand because I hadn't realised how large it is when buying it to setup the tank for them. The barbels on almost all corys are long and nice but there are 3-4 that never recovered them.

I've tried putting lots of alder cones, almond and oak leaves. There were always some in the tank, still fishing the broken up left overs and haven't put any recently. Temperatures went up in the summer now for a good while as usual and there's no difference. How high temperatures should I try? The temp were up to 28C. Normally it's 23-24C

Another thing I forgot to mention. When I tried medicating them last year, I tried the following meds: Interpret Antifungus, Seachem Kanaplex antibiotic and later on Waterlife Myxazin. All these are some sort of antibacterial and they yielded no results in the long run and even short term. I tried lots of water changes too, but it didn't prevent/stop this annoying white ball thing.

I have not tried any antiparasitic meds? Maybe it's a sort of ectoparasite, flukes maybe?

Do you think its a diet thing? Maybe they pig out a lot in this tank. The other unaffected group of corys is in with clown loaches so they can't get that much of the food but these ones eat all of whatever hits the bottom which is daily new life spectrum pellets, protein 37% I think.

[Corycory]

I've been looking at one cory now that has it. Besides the white ball it looks like there's a split in the dorsal as well but the white stuff is not on the split part but on the back side of the dorsal as in the pictures.

Despite that I've never seen any get any permanent damage but maybe it does affect them when they've injured the fin, though there's nothing in the tank that can injure them. Or is it a sort of fin rot that never progresses further than that?

I am uploading a video. Please keep an eye on one of the large bronze corys that has the white ball thing. There are a couple of others with it at the moment, some pass by in the video.

[Corycory]

[Corycory]

Well, it seems I've got to get to a microscope I suppose.

It's odd that there's so little knowledge about fish diseases unless it's something common like ick.

Are there any good books on cory diseases I can check?

[CoryfanAad]

I've seen this earlier with an Albino, but don't know where to find it. In my memory it had something to do with a growth of some kind of bacteria. Temps are okay to me. Sansibar is still under suspecion with me. Still thibk the vulcanic glass of what it is made from, caused "Cory-trouble" although it is said to be Coryfriendly !

[Corycory]

Thanks CoryfanAad.

No, I would never use this kind of sand in a cory tank or in any tank for that matter. I binned it. I had river gravel in that tank for years with no problem and changed it only because of the corys.

So you think its bacterial based on the thread you remember? It would be great if I can find it. All the ones I came across have no ending to the story. On one it was mentioned it could be epistylus which is some sort of harmless parasite.

I am just wondering, if it's bacterial why doesn't it kill them eventually, or spread on the body? It doesn't even cause any damage to them and they've had this for over a year.

[CoryfanAad]

You're right about the bacteria @Corycory . I'll try to find the thread. Don't exactly know on which forum though !!

[CoryfanAad]

Didn't find the thread I meand, but found some others. Could it probably be a virus like Lymphocystis (which doesn't affect catfish I read)?

That would explain why it seems to be untreatable and not lethal aso

http://www.fishlore.com/fishforum/fresh ... p-fin.html

http://www.aquariacentral.com/forums/sh ... Dorsal-Fin

http://www.planetcatfish.com/forum/view ... 16&start=0

Noticed all affected fish seem to be quite healthy-looking as yours !!! Also see Ian's remark in the last post !!!

[Corycory]

Thanks CoryfanAad, very helpful. It's the exact same thing.

My first thought ages ago was Lymphocystis but I also read it supposedly doesn't affect corys. But who knows. It hasn't spread to any other fish and in fact the old tank where these corys were has a group of small loaches and they've been perfectly healthy. I didn't sterilise the tank or change the filters.
I also use the same python between several tanks.
Maybe its just not too contagious or spreads from fish to fish because I have not mixed fish otherwise. But the livebearers with them don't have it.
Also, it doesn't grow bigger and doesn't grow anywhere else, a very selective thing, whatever it is.

Maybe I can try changing the food type in case its diet related as Ian mentioned. I am just not sure what to get them. There's a south American cichlid formula which is just 32% protein. I can get that and also try feeding them less although I don't think I am overfeeding.

[CoryfanAad]

You're welcome. Ass said I noticed it seems to occure with well fed (nice chubby) Corys. So Ian could be right for sure !!!

[Corycory]

Yes, certainly the big chubby ones tend to get it the most I have one runt in the group which never grew big but it never had that. I think changing the food and try feeding less is worth a try for a start.

I'll let you know how it goes.

[Corycory]

Well, I thought I'll update for future reference. Since my last post I tried low protein diet which didn't change anything. By low protein I mean 34%. Then I tried two types of parasitic treatments over a good period of time as instructed, one was Levamisole Hydrochloride, the other was Fluke Solve which is praziquantel in more efficient form.
There was totally no difference and all the fish are alive and healthy, so I am no longer paying attention to those "white blobs" on their dorsal fins. I don't think it's a disease since it's been years now that they've had it. And even if it is, it doesn't seem to kill them. If they live short lives, then I'll know.