Chronic Cory fin rot problems

[josecatala]

Hi,

Just an update to my situation. My 2 Sterbai past on...... I tried Seachem's Paraguard for 7 days as suggested treatment for Fin and Tail Rot. the other 7 seemed to be doing fine, and I thought I may have found the cure, but I noticed today that one of them seem to be showing signs again. I agree it has to me something that is in the setup. A while back I did try Erythromycin as directed and there was a temporary reprieve. All of them seem to be looking for food and eating. I thought about adding Catappa leaves..... I'm interested to see what your results are with Rooibos.

Thanks to all of you and I will keep you posted.

[bekateen]

Good luck josecatala and Mol_PMB.

Cheers, Eric

[ErikO]

I had similar problems with wild caught Sterbai. No problems with their offspring or other locally raised Sterbai.

[Mol_PMB]

Happily there has been a great deal of improvement. All but one of the fish now have normal fins, that one still isn't perfect but has definitely improved in appearance and behaviour.

Here's a photo of feeding time in the tank with many of the fish visible in a mixed species group.

[Daphnia]

Hi, I'm new to this forum and have just seen this post, so, sorry for the late reply. From my experience (a year with 6 Bronze Corys in 30 l planted aquarium in Wales, UK), as soon as nitrate went as high as yours (40 ppm) some of my Corys were guaranteed to have a skin problem of fungal origin, e.g., eroded edge of fin, split fin or a tuft of Saprolegnia. All I needed to do was to perform water changes to reduce nitrate to 5-10 ppm - and all the problems always disappeared in few days without any medical treatment. For the past three months I have kept such low nitrate level, by changing 20% water twice a week, and my pets look happy (even re-growing barbels nipped off a year ago by aggressive serpae-tetras, which I bought by a lack of knowledge and then returned to the shop). I also noticed that the use of a very soft Welsh tap-water (GH & KH undetectable with Tetra test strip) in aquarium favoured outbreaks of fungal pathogens, while creation of a moderately soft water (GH 7, KH 5, which I achieve by additions of CaCO3, MgSO4 and micro-elements of Fe, B, K, Na, Cl) provides for a stable microbial flora in my aquarium. I regularly add autumn leaves (oak, beach, elm and cherry), alder cones and occasionally 1/3 of cinnamon stick.

[Mol_PMB]

Thanks - that's interesting. I also have very soft water (GH 1.5, KH 0.6) but generally keep it that way in most tanks as it is similar to the natural habitat of many of my fish. Perhaps I should add a little coral gravel to raise the hardness a bit?

[Daphnia]

And what about your fish health now? If everything is healthy and stable, I'd just keep it that way, whatever it is based on. We should bear in mind that we keep different species of Corys that may have slightly different requirements. As far as I know, most natural rivers in Brazil don't have such a low hardness as our tap water, which is actually a locally collected rain-water, slightly chlorinated and often contaminated with Cu from copper pipework (the Cu and not Cl2 is the reason why I have to add Bioactive Tapsafe to my water). I checked some data on natural river waters in the internet and also put Tetra Test strip into the river in front of my house, which is highly rated for water quality. The Arth River water test showed: NO3=5, No2=0, GH=7, KH=5, pH=7 - which I decided to set as my target parameters for aquarium. I don't know about coral gravel. I've bought medically pure CaCO3 powder from on-line health store - monthly addition of about 1 gram powder wrapped in a piece of nylon stocking in-between filter sponges gives me KH 5 and PH 7. I've also come across a credible opinion that adding CaCO3 without MgCO3 could be even harmful, as that upsets osmotic nutrient balance in both plants and fish. So, I'm adding also small quantities of pure MgSO4 (Epsom Salt from chemists), Fe, B, K ("I love fish" Plant Fertilizer) and NaCl (sea salt, just one grain a fortnight as a micronutrient), plus whatever micronutrients comes from autumn leaves and alder cones. Sorry I can't tell you exact recipe, just a "cf. idea". And, back to the beginning, low NO3 (5-10) is crucial, according to my experience.

[Mol_PMB]

I've been doing 30% water changes twice a week and have not been dosing plant fertilisers. Two fish still have damaged dorsal fins (which haven't really got better) but their other fins are fine. All the other fish are fine. Apart from the fins, there is no obvious difference in the health of the two fish.
I've got many of the chemicals you mention as I also run a marine tank. I think you're right though, I should also focus on more water changes and keeping the nitrate down. I probably over-feed this tank too as there is an abundance of snails.
Most of my other tanks run with similar parameters and the other spcies of Corydoras I keep in them don't have such problems.
Thanks for your thoughts.
Paul

[Daphnia]

Thanks you, Paul, for explaining your situation, it is very useful for me to know about your experience, for there aren't many aquarists dealing with so soft tapwaters like ours.
If all your fish are fine, except the two, then it looks like the two fish just have a weaker immunity than the others. Have you tried to feed them up with some live foods? - Known as the best source of essential amino acids and whatever fishes need to be healthy, and I suppose that at least bloodworm should be available in such a big city as Manchester. Here I am in a very rural place and local pet stores are quite poor in fish supplies. I'd love to provide some natural treats for mine, see them happily slurping up worms... But so far I've just started with home-bred daphnia. If you can pass a comment on that, please, switch to my subject "Live daphnia for Corydoras".
Best regards,
Inga

[Mol_PMB]

Hi Inga,
Thanks again

Yes, they get live foods quite regularly. I keep cultures of Microworms, Grindalworms, Daphnia, Moina, Artemia, Copepods and Rotifers. Sometimes I buy bloodworms, blackworms, whiteworms, tubifex and 'glassworms' (mosquito larvae). This tank of Corydoras gets live Grindalworms about two or three times a week, with other feeds being JMC high-protein catfish pellets or frozen bloodworms. My Cories love worms but and other foods that sink, but don't tend to chase the live foods that swim.

I've had a bit of a shift around recently and have now got three tanks of Corydoras; I tend to keep them in groups of similar-looking species:
90L: 8 C. oiapoquensis, 3 condiscipulus and 1 amapaensis (the one with the fin problems)
100L: 13 C. melini, 3 simulatus, 2 C016 (plus some Copella meinkeni and two juvenile Pangio loaches)
54L: 6 C. burgessi plus fry (spawning almost weekly at the moment)
Nearly forgot, all my tanks also have at least one juvenile Farlowella vittata as a glass-cleaner. I'm over-run with them!

I believe that all my Corydoras are wild-caught except some of the oiapoquensis (from a local breeder), one melini (born here) and the growing herd of burgessi fry.

Regards,
Paul

[Daphnia]

Sounds great. I have looked up the images of your fish species in the internet, very exotic indeed. You are lucky. Adaptation of new species for captivity is so interesting, challenging and important for conservation of rare species, some of which are not yet identified, but already endangered - I've read some articles in Practical Fishkeeping. I do feel amazed.
Could you, please, advise me on a type of worm that I can grow in my garden/polytunnel during summer? (our house is really small and I am not allowed to bring in worms.) and, if such worms exist, could you send me some eggs by post? I don't need many, as I only have 10 small fish (6 Bronze Corys + 4 Harlequin Rasboras), which I want to treat with live food twice a week for mutual entertainment and supporting their health (with no intention to breed, as there is no space for that here).

[Mol_PMB]

I'd say you could keep microworms or grindal worms in those conditions during summer.

Here's a thread I wrote (on a different forum) which includes a description of how I keep both of these types of worms:
http://www.tropicalfishforums.co.uk/ind ... 402.0.html
The challenge when keeping them in the garden would be to keep the other wildlife out so you would need some very fine mesh over the holes in the boxes.

I could easily send you small packets of either (or both) types of live worms to get you started; you'll need to get the rest of the ingredients.

Drop me a personal message with your address and I'll send some this weekend.

Cheers,
Paul

[Daphnia]

Hi Paul, I've prepared homes for the creatures. I've also enjoyed the videos of Corys in their natural habitat you posted earlier. And I've tried to think of possible explanations why a slight mineralization of water has worked for my aquarium. There are two:
1) It is believed that KH > 80 ppm (4.5 d) is needed for sufficient buffering capacity in planted aquaria to prevent pH swings day-night due to CO2 coming from respiration of plants at night. Such pH swings can stress fish, at least weaker individuals [info from the internet].
2) In soil science [my profession] the biological activity of soil is characterized by fungal:bacterial (F:B) ratio, and the lower soil pH the higher this ratio. Just an idea, what if there is a similar interplay in aquaria, with F="bad" fungal pathogens, b="good" nitrogen bacteria (lower pH - more pathogens?). This suggestion seems to contradict the fact that microflora copes well in soft acidic waters of South America. However, maybe just our commercial N-cycle bacteria (designed for average H parameters, would that matter?) get sometimes outcompeted by local fungal pathogens in soft acidic waters. Another observation on F:B ratio comes from my garden: I've successfully cured fungal diseases of few plants by dressing soil with CaCO3:MgSO4=3:1.

[Mol_PMB]

I won't get a chance to get to the post office today, but I'll send them to you tomorrow. Hope that's OK.
Cheers,
Paul

[Daphnia]

Hi Paul,
Of course, tomorrow or so, will be fine. Just drop me a message, please, when you manage to send them - and I'll be waiting for the postman the next days.
Maybe my F:B ratio hypothesis sounds crazy, but I'd appreciate if you tell me exactly what you think, doesn't matter - for or against - I only want to find the truth for myself. I think that good and bad microorganisms are in constant competition for colonising every substrate in aquarium (filter, gravel, plants, fish skin), and if the good ones are encouraged to squeeze the bad ones out of the water completely, then fish has a better chance to supress their skin pests by their own immunity. Medications used to eliminate the baddies can also stress fish and thus undermine their immune response. A small and gradual increase in hardness, as a temporary alternative remedy, should not cause as much stress as medications, am I wrong? By the way, what are your impressions from using phenoxyethanol (Interpet Anti Fungus and Finrot)? Did you notice any side effects? Nobody was too sedated?
Best regards,
Inga

[dw1305]

Hi all,

It is believed that KH > 80 ppm (4.5 d) is needed for sufficient buffering capacity in planted aquaria to prevent pH swings day-night due to CO2 coming from respiration of plants at night. Such pH swings can stress fish, at least weaker individuals.......

It isn't actually true for fish from soft water.

Tanks with some dKH are easier to manage, but you will always get some diurnal variations in pH in planted tanks, even ones with heavily carbonate buffered water. Changes in pH caused by changes in the oxygen:CO2 ratio don't actually change the alkalinity of the water, you've just moved the CO2~HCO3-~2CO3~pH equilibrium point.

I only keep planted tanks, because plants massively help with water quality management.

Fish from soft water will always experience fluctuations in pH and, as you move towards pure H2O, pH becomes a fairly meaningless parameter.

The only way to ensure a really stable pH is to use a pH buffer, (usually based on NaH2PO4:Na2HPO4 (conjugated acid and base)), and that is a pointless, and self-defeating, approach.

2) In soil science [my profession] the biological activity of soil is characterized by fungal:bacterial (F:B) ratio, and the lower soil pH the higher this ratio. Just an idea, what if there is a similar interplay in aquaria, with F="bad" fungal pathogens, b="good" nitrogen bacteria (lower pH - more pathogens?). This suggestion seems to contradict the fact that microflora copes well in soft acidic waters of South America. However, maybe just our commercial N-cycle bacteria (designed for average H parameters, would that matter?) get sometimes outcompeted by local fungal pathogens in soft acidic waters. Another observation on F:B ratio comes from my garden: I've successfully cured fungal diseases of few plants by dressing soil with CaCO3:MgSO4=3:1.

Very soft, acidic "black water" has a very low microbial load, and that is one of the reasons that black-water fish are difficult to keep in harder water.

There is quite a lot of recent (RNA based) work on the nitrifying organisms in aquarium filters, and it has shown that these communities are a lot more diverse than had initially been suggested.

You could have a look at "PlanetCatfish: Cycling Question"(viewtopic.php?f=4&t=41965)> and "PlanetCatfish:Using deep gravel...." (viewtopic.php?f=4&t=41038) for a more in depth discussion.

cheers Darrel

[Daphnia]

Thanks again, Darrel! Hydrobiochemistry discussions in these links are really in depth, very interesting and I'll have to spend more time on those. There is a similar tendency in soil science to reveal more and more complex interactions in soil biota. I still don't understand, what goes on in my aquarium with all those minerals, but I will try for experiment to gradually decrease my complex mineralization. After all, it is likely that my fish used to have skin problems because of lowered immunity due to a lack of nutritious food, and there was nothing to do with hydrobiochemistry.

[Mol_PMB]

Thanks Darrel!

[dw1305]

Hi all,

Thanks again, Darrel! Hydrobiochemistry discussions in these links are really in depth, very interesting and I'll have to spend more time on those. There is a similar tendency in soil science to reveal more and more complex interactions in soil biota. I still don't understand, what goes on in my aquarium with all those minerals, but I will try for experiment to gradually decrease my complex mineralization. After all, it is likely that my fish used to have skin problems because of lowered immunity due to a lack of nutritious food, and there was nothing to do with hydrobiochemistry.

The simple answer is that we just don't know what is happening in the tank.

Diana Walstad has some data in "Ecology of the planted aquarium" (if you don't have a copy I would strongly recommend it)
(https://www.amazon.co.uk/d/Books/Ecolog ... 0967377366) and there are articles by Dr Stephan Tanner (http://www.swisstropicals.com/library/a ... iltration/) & Dr Tim Hovanec (http://www.alltropicalfish.com/saltwate ... a-revealed) & (http://www.drtimsaquatics.com/resources ... ogen-cycle).

There has been quite a lot of scientific work of "constructed wetlands" for waste water treatment, some of which specifically deal with aquaculture, and we could conjecture that similar processes are likely to be occurring in planted tanks.

cheers Darrel

[Mol_PMB]

Interesting stuff, many thanks!

Happily there are no fin rot problems in my Cory burgessi tank, although I do find that the majority of eggs go fungussy. Here's a cute shot of the only survivor from their first spawn (which I didn't segregate). I have five more half-inch fry from a more recent spawn in the nursery and hoping the adults spawn again soon.

[Daphnia]

a cute shot of the only survivor from their first spawn

Very cute indeed.

[Daphnia]

Diana Walstad has some data in "Ecology of the planted aquarium" (if you don't have a copy I would strongly recommend it)
(https://www.amazon.co.uk/d/Books/Ecolog ... 0967377366) and there are articles by Dr Stephan Tanner (http://www.swisstropicals.com/library/a ... iltration/) & Dr Tim Hovanec (http://www.alltropicalfish.com/saltwate ... a-revealed) & (http://www.drtimsaquatics.com/resources ... ogen-cycle).

Darrel, thanks for interesting links. I've read the articles and maybe will get the book one day. I didn't know that there is no Nitrobacter, but Nitrospira converting nitrites to nitrates in aquariums.

Paul, in connection with fungal growth, I'd like to share my observation on alder cones. Some, which I put directly into aquarium, are remaining always free of fungus, gradually turning from light to dark brown over couple months till they almost completely decomposed and I bury them into the gravel near to plant roots. The others, which I put in the jar to infuse the tap water to add into aquarium upon water change, are undergoing a different scenario of decomposition: in two weeks they start to turn black and get overgrown with white fungus and I throw them away. So, for alder cones, there is bacterial decomposition in aquarium water and fungal in tap water. Did you notice the same with your alder cones?

Inga

[Mol_PMB]

That's interesting about the alder cones. I wonder if it's to do with water circulation and perhaps the availability of oxygen? I've noticed the gradual decomposition in my tanks. When I soak leaves, alder cones etc in a bucket to make black water, I usually have an airline bubbling in there.

[Daphnia]

That's interesting about the alder cones. I wonder if it's to do with water circulation and perhaps the availability of oxygen? I've noticed the gradual decomposition in my tanks. When I soak leaves, alder cones etc in a bucket to make black water, I usually have an airline bubbling in there.

I used to blame the absence of minerals, then the absence of N-bacteria to colonize the substrate before the 'whitish fluff' grows on it, but now I see you are right - it is surely because of absence of circulation, for you haven't got that thing because of the airline bubbling. The 'whitish fluff', to be honest, doesn't really look like fungus, but rather like local bacterial bloom feeding on exudate from those cones... However, my cones in a jar stay in very small amount of water, just to cover them up, so there couldn't be a lack of oxygen. Next I'll try to seed some N-bacteria in such jar and see if that makes any difference. Can N-bacteria colonize if there is no circulation, but probably enough oxygen - I'll see.

[dw1305]

Hi all,
Have you seen: "Medicinal trees:Common Alder": (https://www.aqualog.de/en/blog-en/medic ... mon-alder/)?

There is quite a bit of scientific work on the anti-microbial effects of Alnus species as well.
From "Antioxidant, cytotoxic, and antimicrobial activity of Alnus incana (L.) ssp. incana Moench and A. viridis (Chaix) DC ssp. viridis extracts."

....... In our experiment all extracts were virtually nontoxic on brine shrimps. Extracts were screened for activity against 15 microorganisms, and all extracts investigated showed antimicrobial activity. The most active were dry extracts of cones of A. incana and A. viridis with minimum inhibitory concentration values ranging from 0.117 to 0.129 mg/mL.

and "Antimicrobial and cytotoxic activity of Alnus glutinosa (L.) Gaertn., A. incana (L.) Moench, and A. viridis (Chaix) DC. extracts".

......Potential antimicrobial properties of A. glutinosa, A. incana, and A. viridis demonstrated in this study, as well as their low levels of toxicity, make them an interesting subject for further studies.

cheers Darrel

[Daphnia]

about the alder cones.

Hi Paul,

the alder cones after 2 weeks of being soaked in 100 ml water with 1ml of Filter Start, say, a huge dose of N-bacteria, are still missing the white fluff. I've also been changing the cones' water twice a week, as I added the infusion with water changes into the aquarium.

Sorry for the mineralization mess in previous posts, now I've completely re-thought the explanation. Firstly, I've read that finrot isn't fungal, but caused by one of several bacteria stains. Then, in my aquarium, for the first two months (last June-July) many cases of finrot were just a period of adaptation to the new aquarium, with mineralization being just a benign thing, but as I thought it was helping good bacteria to establish and squeeze the bad ones out - of course I was seeding huge dozes of Interpet Filter Start. I did the same during occasional finrot cases over autumn and winter, and now reached a long-desired fin-rot free stage (probably because I've finally learned to keep nitrate low). Saprolegnia was only the last June-July and never since. But, still, two Corys have a problem of chronic barbel erosion, which comes and goes so that barbels haven't got a chance to regrow properly. Probably live foods isn't the only measure I can take. I'll decrease my mineralization (GH from 7-8 down to 1-2 of tapwater), but not before I go to Russia next month, just after.

I wonder are there any news about your 2 Oiapoques with the finrot problem? Any better?

[josecatala]

Hi Everyone,

I know this is an old post, but I thought I post an update on my corys in my 72 gallon from a year and half ago. Out of the 7 remaining bronze ones, 5 ended up dying.... all with loss of barbels and fin rot. No matter what meds I tried, how many times I changed the water, nothing worked. The last two for some reason didn't succumb to what ever it was. They are still alive and doing reasonably well. Their barbels are still short and have not grown back. From time to time I notice the start of fin & tail rot and the shorting of the barbels from time to time and I would treat the tank with paraguard from Seachem for 7 days. That seemed to stop the fin rot. The parameters in the tank are all good. Angelfish breed every two weeks and I have not had any other loss of fish. But....
about two months ago, I took some plant trimmings from this tank and put it into two of my other tanks and now I noticed that there is the start of barbel loss on a couple of other cory cats. I don't know if its a coincidence or not.
but I'll start treating those tanks also with paraguard. Only difference, is I'm going to do it for 2 weeks instead of 7 days. I'm now wondering if this could be a type of parasite. Paraguard says it does treat ectoparasites. The 2 corys in the 72 gallon will be 5 years old in Nov. of this year. The other two are probably over 2 years old. Hard to tell with so many of them in the tanks. I'll post the outcome in a couple of weeks.