Cory Fry Dropping Like Flies!

[MHunt]

Just wondering if anyone has any ideas. My 10 gal tank with cory fry in has succumbed to some kind of infection, i can't tell if it is bacterial or parasitic. I first thought some kind of leeches or flukes as they has white stringy things coming off them. This has gradually spread to most of the fish in the tank. I'll be honest i haven't tested the water recently, and i haven't done a water change as i've been giving the meds a chance to work. I am now treating with sterazin for my original thought of some parasitic infection, myxazyn to help the wounds to heal and protect against secondary fungus, and melafix, again to aid in healing the wounds.

Will the meds affect what kind of reading i get from the water test kit? I need to continue the sterazin till sunday, then beginning of next week i'll do a large water change, clean the filter etc. I also have like a grey scum on top of the filter, and starting to appear on the glass. I'm really at a loss as what to do next. I'm prepared that i might loose the lot, but i do want to save as many as i can. The one's i have put in my community tank are doing really well, growing well and with a great colour. The parents are still spawning readily so i can try again if things go completely, but if i don't know what happened, the same thing may well happen again!

 

[WILDER]

Corys are not prone to parasites more bacterial.
Where are the strands on the corys as it can be bacterial.

 

[MHunt]

All over really, from the fins, the sides, the head. stringy like in attack of the body snatchers. Almost like little tape worms coming from under the skin!

If it is bacterial, what is the best course of treatment, i have some interpet 9, internal bacteria, and 6 whitespot treatment, also waterlife sterazin and myxazyn, finally some melafix. I know interpet do an external bacterial med, and is it waterlife protozin that is better for bacterial infections? I'm not to bothered about wiping out the filter bacteria colony in the process, the fish are dead anyway without an effective treatment.

 

[WILDER]

Do the stands have a forked tail, does it look like string or parasites.
Added any new plants lately.

 

[MHunt]

I thought about the parasites with the forked tail you've mentioned before, but they look more like white stringy bits. I did think about tiny white leeches, but i wouldn't like to think about how they got there as i drink the same water supply!

I did add some plants, but only recently in an attempt to absorb any excess nitrate there may be in the tank, try and improve the water quality. They were from my community tank which is totally healthy.

 

[WILDER]

So the strands do look like a parasite, are they moving.

http/www.fishpalace.org/anchorworm1_jj4himsympaticoca.jpg

 

[MHunt]

Not that i can see, and they perhaps become more prolific more quickly than a parasite could reproduce. They're not the anchor worm, and they dont appear to move independently. I am continuing with the myxazyn and melafix. The last dose of streazin is tomorrow so i might as well do that, couldn't hurt but doesn't appear to have had much effect.

I'm going to do a large water change today and really clean the tank, the filter casing, decorations etc. probably catch the fish into another tank or bowl so i can really disturb the tank and save the fish i can. I may even euthanise the worst ones to save the most healthy.

 

[NEONCORY]

I am not an expert about the parasite or bacteriaand such. But I am curious about the detail of the set up(substrate and plants) and size/age/specie of the frys and type of food.
These additional information may help for someone to diagnose the cause.

I am growing Panda and Sterbai frys and I notice that I find some hydra get into the tank. And I recall that they tend to appear when you use the live food. I don't use the BBS yet but I have been using vinegar eels and walterworms. And the frys are 2~3 weeks old. I don't think the hydra would harm my cory frys but I don't know what to do. Since I have some Cherry red shrimps and snails in it for baby sitter. And I think the medication for the hydra would harm shrimps.
And I also believe the frys get bacteria more often from the bare bottom tank than tank with thin layer of sands. I think bare bottom does not work well for the bottom fish.

I am sorry this is not the answer for your problem but it is something I experienced growing some of the Cory frys.

I hope someone can give you good answer.

 

[MHunt]

The latest setup is an AquaOne 320. 28 Litre (10 Gal ish) tank. I have had as many as 40 fry in this tank as they have been growing. The tank is filtered with a fluval 2+ using the normal sponge pads. The temp is kept at around 26 degrees C. The tank has a sand substrate (first time i've used one) and did have a few plants until i stripped the tank down for a good water change and clean today. Decor was sparse apart from three ceramic plant pots taken from my garden like the ones used in my community tank. My feeding regime was originally baby brine shrimp and liquifry powder which has been successful. More recently i have stopped the brine shrimp and started on broken down normal tropical fish food.

The fry themselves are normal Corydoras aenus, bronze cory's. They are a couple of months old now. I do have a control for comparison, i removed three of the fry into my community tank a few weeks ago, they have flourished, they surprised me today as to how big they are now. They have done much better than the ones growing on in their own tank.

My suspicion is that i have not kept up a good maintainable regime in their tank, allowed the water quality to drop through infrequent water changes and overfeeding. Once the fish started to get sick and die, not all have been found till recently so that would have polluted the water further causing more illness. But you live and learn. I have cleaned the tank thoroughly, it has probably had a complete water change, but I really want to start fresh. The fish are out in a tub of their old tank water at the moment but floating in the top of the tank to keep the temperature up. I may even select the few least infested ones to keep, and euthanise the rest. I know it is not a nice decision, but i'd rather save a few than loose the lot.