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FAQs on the Minnows called Barbs, Danios and Rasboras Disease 3

Related Articles: Barbs, Danios & Rasboras, A Barbed Response; Wrongly maligned for being fin-nippers, barbs are in fact some of the best fish for the home aquarium by Neale Monks

Related FAQs: B,D,R Disease 1, B,D,R Disease 2, B,D,R Disease 4, Barbs, Danios, Rasboras 1, Barbs, Danios, Rasboras 2, B,D,R Identification, B,D,R Behavior, B,D,R Compatibility, B,D,R Selection, B,D,R Systems, B,D,R Feeding, B,D,R Reproduction,


Danio O' Danio; disease      8/18/17
Good day!
<Hello Samantha,>
I've been reading about with many different forums, and probably passed a good hour of my time browsing through the zebra Danio illnesses you have all replied to, but still seemed to be unable to find a bit of a bizarre problem I've been having with my own Danio. (Or Danios I should say.)
<Fire away.>
SO. I'll start you off with a walk through the Danio plagues, maybe they're all connected....
<Or not.>
I've had this tank for a year, 75 gallons understocked, and I have gone through a total number of 24 Danios. All but one didn't survive. The poor quality of the lfs in my area probably have a big role to play, that's why I got my lone survivor from pet smart. Anywho. All died while I was gone, and they'd act fine before dying. I assumed they picked each other off.
<Does happen, though rarely with large groups of Danios; by contrast, get six, and yes, they can 'worry' each other to death, winding up with a single dominant fish left over.>
I never had a problem with any of my other fish in the tank dying. But it was my last batch of Danios that concerns me. It looked like they had parasites to me.. but they died too soon for me to be able to do anything about it. They'd get the beginning of an ulcer, and the next morning I'd come back to a munched on carcass.
<Which is, of course, a good way for pathogens to get transferred... When dealing with a situation where one fish dies, then another, then another -- sometimes it's a good idea to remove the next ailing fish, humanely destroy
it, and then see if that stops the process (ideally, alongside some sort of appropriate medication).>
My read rainbow got a fungal growth on its side and had labored breathing with difficulty swimming, so i amped up the amount of air in the tank and added tank salt until he healed. Took about a week. I'm not a fan of medicating, I'd rather let the fish heal on its own, unless it's severe.<Understandable, but in some cases, the fish can't heal, and you need to act quickly to "nip the trouble in the bud".>
A few days after my rainbow recovered I noticed an ill Danio. I personally thought it had dropsy. Swimming in tight circles, pine coning, bloat; but when I fished it out and dropped it into the toilet it exploded out the sides... it looked like intestines, but could have been parasites.
<Or simply Dropsy; pressurised decomposition; tissues of deceased fish giving way on impact, releasing that pressure...>
Gross. I did a 75% water change and kept a close eye on the other fish. 1 Danio left. (Mind you she survived every other plague among the Danios.)
Now she's always been a bit plumper, but after the death of the other Danios, she just looks bloated. And she's been this way for months. I've given her peas, did heavy water changes, laid off the feeding... Three days of no food made her look a bit better... but not by much. She swims perfectly, likes to play in the current, and eats like a pig. Seeing as she only has three other fish to compete with for food. No rising scales, no lumps, only one smooth bump.
<Indeed. Doesn't look like classic Dropsy, but could well be intestinal
parasites, but also something like a Mycobacterium infection.>
Here, have a gander:
I feed her a mixture of meaty foods; brine shrimp, krill, blood worms, etc.
Sometimes they nibble on the remains of a chopped up dunia roach for my frogs... They really won't touch flake food much anymore.
SO any thoughts??
<Identifying what exactly when wrong here is impossible to say. The symptoms are too generic. So my gut reaction is that you were unlucky, perhaps buying a bad batch of Danios infected with Fish TB or similar. If the remaining species are fine, I'd leave the tank at least a month, and see if anything else gets sick. If all is well, I'd probably try something that wasn't a Danio -- or at least, wait until another batch of Danios arrives at some other store, so that you don't have a repeat performance. So far as medication goes, perhaps running a broad spectrum antibiotic
might be useful, or an equivalent product like eSHa 2000.>
I really appreciate your help!
<Welcome. Neale.>

Columnaris Denisoni Barb/Redwag Platy        9/30/16
I noticed one of my denisoni barbs, and Redwag Platy had lesions, which I assumed was Columnaris.
<Mmm; maybe.... what re cause here? Such infections don't occur w/o environmental prompting>
I did a lot of research and the common theme, I found, in treatment for Columnaris was reducing temperature, salt, KanaPlex, MetroPlex, and furan2.
I moved the barb and platy from my 75g to my 10g hospital tank, and began medicating the water with furan2, salt, and feeding KanaPlex/MetroPlex.
The platys dent/lesion has lost the white line in the dent, and seems to be doing fine. My barb, on the other hand, developed even more lesions, but is very active and eating well.
For the second round of medications, I medicated the water with furan2, salt, KanaPlex/MetroPlex (I did not dose food).
I repeated the first round of medication, making it 3 total rounds of medication.
My barb has not developed any new lesions for about 5 days, and my platy looks normal. My question is when do I know my barb and platy are healthy enough to go back into my main tank?
<I'd wait a good few weeks beyond when these "lesions" are gone>
I've had them in my hospital tank for 3 weeks, and I feel the barb (4.5inches) is getting a bit stressed in the 10gal, and without his school.
Thank you!
<Keep changing some (a few gallons) of water daily... From their main/display system. Bob Fenner>

Columnaris Denisoni Barb/Redwag Platy     /Neale       10/1/16
I noticed one of my denisoni barbs, and Redwag Platy had lesions, which I assumed was Columnaris. I did a lot of research and the common theme, I found, in treatment for Columnaris was reducing temperature, salt, KanaPlex, MetroPlex, and furan2.
I moved the barb and platy from my 75g to my 10g hospital tank, and began medicating the water with furan2, salt, and feeding KanaPlex/MetroPlex. The platys dent/lesion has lost the white line in the dent, and seems to be doing fine. My barb, on the other hand, developed even more lesions, but is very active and eating well.
For the second round of medications, I medicated the water with furan2, salt, KanaPlex/MetroPlex (I did not dose food).
I repeated the first round of medication, making it 3 total rounds of medication.
My barb has not developed any new lesions for about 5 days, and my platy looks normal. My question is when do I know my barb and platy are healthy enough to go back into my main tank?
I've had them in my hospital tank for 3 weeks, and I feel the barb (4.5inches) is getting a bit stressed in the 10gal, and without his school.
Thank you!
<Bob Fenner has covered the essentials here. But a couple extra comments if I may... For a start, do understand this species subtropical. At tropical temperatures it isn't entirely happy, and in particular low oxygen levels and high nitrate levels will stress them. If the tankmates are Platies, which are perfectly happy in cooler conditions, I'd be keeping this/these species around 22-24C/72-75F rather than anything warmer. Optimal conditions for Denison Barbs is likely a few degrees cooler than this. Let me have you read the Fishbase page on this species, here...
Certainly optimise water circulation and oxygenation, though I will state that Platies are still-water fish, and will not thrive in the brisk currents Denison Barbs need (though Swordtails, being stream-dwellers, would actually be pretty decent companions). Secondly, I'm not sure adding salt is terribly helpful. Barbs vary in their tolerance for salt, some actually inhabiting low-end brackish habitats, but these barbs are definitely inland fish, and I can't see any advantage to even trace
additions to salt unless you're dealing with something specific where salt is the cure (like Whitespot). Instead, I'd be coupling a general purpose antibiotic alongside an aggressive approach to optimising water conditions.
Denison Barbs have, overall, a poor to middling track record in captivity; relatively few reach their proper size and live anything close to a full lifespan. Read, review, and act accordingly. Cheers, Neale.>
re: Columnaris Denisoni Barb/Redwag Platy      10/1/16

Thank you for the quick answers!
I am going to remove the platys (3) and move them to my 20g long because there is substantial water movement with an AquaClear 110, 520gph canister filter, and an 325gph hydroponic air pump.
<Sounds wise.>
The issue might have been temperature (I do two 50% water changes a week on the 75g), as summer just ended here and my tank has been at a constant 80F for 3 months.
Should I look into re-homing the barbs if I cannot consistently maintain a lower temperature throughout the entire year?
<Nope. Summertime highs are fine. The issue is year-round high temperatures. Basically, the ideal approach would be to allow the tank to warm up in summer, but during the winter make sure it cools down a bit, so there's some seasonality. This will be much closer to "the wild" and ensure your Denison Barbs stay healthy. Lows of 15 C/59 F are probably not
necessary, but something like 20-22 C/68-72 F would be beneficial, and still allow a wide variety of tankmates. Many barbs, Danios and minnows, many loaches, numerous Loricariids, most Corydoras, and a few cichlids (like Acaras) and livebearers (such as Swordtails and virtually all Goodeids) prefer precisely these conditions. Bronze Corydoras and
Bristlenose Plecs are two examples of widely sold and inexpensive fish that would thrive in a riverine tank adapted to Denison Barbs.>
Thanks again!
<Cheers, Neale.>

Danio with open sore on side, curious if it's from eggs.        1/13/16
Hello WetWeb! Jamie here,
<Hello Jamie,>
Your website has proven incredibly informative and you have helped us understand issues on our tanks countless times in the past. Thanks for your excellent and unsurpassed work. You've addressed a very similarly injured Danio in the past, and I'm wondering if it's something I discovered called EAIF.
<According to Google, "Emerging Africa Infrastructure Fund"... which doesn't sound like what you have in mind here...>
BUT per standard WWM procedure here is a history/tank condition summary. We have a relatively new tank (I know that's a dreaded phrase) been up about 3 weeks with a fish in cycle. We have a dirted/soiled tank that is medium planted and we're working towards heavily planted. It's a 60 gallon tank (high build rather than long) with 2 surviving Serpae Tetras,
<Nasty, nippy fish. Choose tankmates for these extremely carefully.>
1 juvenile peacock eel,
<Difficult to feed; short-lived unless they get regular offerings of frozen bloodworms and other small meaty items. Will also get damaged by gravel, so be sure the substrate is soft enough they can dig easily. Scratched bodies quickly become infected... then they die.>
8 new addition Amano shrimps to help with tank clean up, and 10 surviving Zebra Danios. Water changes have been frequent and we test with API freshwater kit. Ph matches our local water source at about 8.0. Ammonia had one spike after we first changed to a dirted and medium planted tank about 2 weeks ago. We do water changes if the ammonia reads .25 or higher.
Nitrites and Nitrates are both 0.
<Nitrate at zero seems unlikely.>
We got the Serpae Tetras in a school purchased from a pet store chain we've had previous bad experiences with (a few years ago when we last kept tanks) due to fungal infections and so forth. We were giving them one last chance.
With the fish in cycle and the poorly kept fish to begin with developed various symptoms and we lost 9 within a week of purchasing them, some appeared to have a fungal infection so we treated with an anti fungal which left us with the 2 survivors. Prior to adding the tetras we had 6 Danios in the tank, and all but one that was purchased with a curved spine, were doing fine. I apologize for the lengthy history.
Now for the reason I'm writing. We noticed the fish with the curved spine got noticeably rounder in just the belly area (no pine-cone scales) and she had what we assumed was a gravid spot. We have no experience with egg layers, only live bearers like guppies. We assumed she would just lay her eggs, but day by day she got a little larger and then a sore appeared on her side under her fin.
<Physical damage, perhaps exacerbated by fin-nipping is likely here. Danios are fairly boisterous towards one another, and physical damage is not uncommon.>
The next day it looked like it was healing, so we assumed she had just bumped something. We watched her and she was behaving normally. The next day she had a much larger sore on the other side under her fin. She died that night. Thinking it was just the stress of the new tank and the curved spine showing genetic difficulties already, we weren't too concerned.
<While a bent spine can be genetic, such traits are obvious from birth. If the spine becomes bent after you buy the fish, the chance is more likely something else... poor diet, exposure to toxins, that sort of thing.>
We later had another Danio develop a similar small sore on one side, which then healed over. An additional sore showed up on the opposite side, and healed over again. Now this same poor fish has a huge sore on one side. We looked on wet web media and found that Neale advised someone named Audrey who provided a picture with an extremely similar sore and said it appeared to be an ulcer. Neale advised to find out how this fish got injured twice and to treat as you would for Finrot. Which we'll do asap for our injured Danio.
<Good move. Provided only muscle and skin are damaged, fish often recover from quite severe wounds. Anti-Finrot medications are what you need here.>
My curious nature and being anxious to help my fish as best as possible led me to another website which has another picture with an almost identical sore, again. Have you ever heard of Egg Associated Inflammation (EAIF)?
(Here is the link I found http://zebrafish.org/health/diseaseManual.php
clicking on Egg Associated Inflammation will show the similar picture I was talking about.) Could this be what is going on with our poor fish?
<Possibly, but it's pretty rare. Fin-biting and/or physical damage are more common. For example, a startled fish throwing itself at a sharp piece of metal on the hood, or a jaggedy piece of rockwork. Looking at the "Egg-Associated Inflammation" photo, it would seem that the swelling comes from the inside, forcing the abdomen outwards, eventually tearing the skin
tissue, and that becomes the external wound. So is this what you're looking at here? Swelling first, wound later? That's different to Finrot or external ulcers, where there's a cut or wound of some sort, and then bacterial infection sets in.>
I'm not great at understanding science lingo, but it sounds like the eggs essentially force their way out of the side of the fish if the fish can't spawn correctly? This sounds absolutely horrifying!
<And rare. The gist of the article is that the eggs aren't expelled (for whatever reason) and as they decay inside the ovaries they create a swelling mass of some kind. These can become infected but bacterial infection isn't the cause. Anyway, after a while the mass is so big it comes out through the skin. Danios spawn readily, even in community tanks, so "egg binding" just isn't something that I've seen or heard of in them.
But clearly it happens, and perhaps more often than we thing. Some cases of dropsy or tumours might well be this. In any event, untreatable directly, though Epsom salt dosed at 1 tablespoon Epsom salt per 5 US gallons/20 litres aquarium water is pretty good as a laxative of sorts, and this can help with egg binding in fish and other animals.>
We'll treat the fish for Finrot per Neale's previous suggestion and try to set up spawning conditions. Just wondering if you could provide any insight to the likelihood of this being what's going on or not. I know that the tetras dying is far from a good sign in itself, and new tanks/fish in cycles are hazardous conditions so I'm not ruling that out as a problem.
Thanks again for your work and your time!
<Hope this helps. Cheers, Neale.>

Illness in Glofish Danio      12/1/15
Hi crew,11 days ago I noticed that one of my five GloFish Danios had a red spot between his fin and tail on one side. Two other GloFish Danios seemed to have red gills, but I couldn't tell if they were redder than normal. I also have cories, tetras and Kuhli loaches in this tank who all seemed to be unaffected.
<I see>
The only thing I knew for sure was that my blue GloFish with the red spot was definitely ill. One of his fins was also in a contorted position and he wasn't eating.
<Well; these Glofish varieties of Brachydanio are not as hardy as their wild-types>
The water parameters were the same as usual - 0 ammonia, 0 nitrates, 10 nitrites, 6.8 pH. I chose to treat with MelaFix
<I would not.... has no real use, action. Can/does contaminate the water; interfere w/ nitrification>
since it was the only thing I had on hand. I saw improvement within 2 days so I continued with the MelaFix. The red spot on my blue GloFish lightened daily after treatment and his fin regained normal function. I followed the 7 day treatment plan and continued as needed since the spot wasn't completely gone. After 11 days I missed 2 days of treatment since I was away for the holiday. Now I've noticed that my blue Danio is starting to develop the spot on his side again. The water parameters are the same except the pH has shot up to 8.2!
<?! How is this possible?>
I'm guessing this was caused by the MelaFix??
<Have never heard of this effect. What is the pH of a drop of this API scam in a test of water?>
I haven't made any other changes to the tank. Should I continue with MelaFix or try a different product?
<I would not treat this symptom period; but instead do what I can/could to improve water quality (water changes, gravel vacuuming, use of carbon...) and nutrition>
Please help if you can offer any insight! Thanks so much! Danielle
<Mmm; I'd like to have you read re Danio disease: http://www.wetwebmedia.com/fwsubwebindex/zebraddisf.htm
My strong intuition senses there's "something missing" in our discussion here. Foods/feeding?
Bob Fenner>
Re: Illness in Glofish Danio       12/5/15

Hi Bob, Thanks so much for the response. I wanted to wait a few days to give you the most accurate update possible.
<Ah, good>
My plain tap water has always(and still) has a pH of 7.8.
<This is fine for Danios (in fact, most all aquarium organisms)>
My tank has also been reading 7.8 daily since we last spoke, which is no surprise since I've been doing 10% water changes daily. I've discontinued the MelaFix as well.
My blue GloFish Danio still has the red spot on his side but it hasn't gotten any better or any worse. You said it was unheard of for the pH To shoot up the way it did due to MelaFix, so I'm searching for another reason. It could be partially due to the 25% water change that I did after the first 7 days of treatment with the MelaFix. I also add a tsp of baking soda and a drop per gallon of calcium chloride to my new water.
<Mmm; well; sodium bicarbonate could be the cause here.... it will/DOES raise pH to about 7.8; and act as an effective buffer at that "point">
If I don't, my kH and gH would read zero.
<Mmm; do please read Neale's excellent piece here: http://www.wetwebmedia.com/fwsubwebindex/fwh2oquality.htm
You can, should either make or buy a commercial prep. that will add Calcium, Magnesium, and likely some carbonate to your water (ahead of use)>
I also started feeding my fish a frozen variety food that includes plankton, brine shrimp, meal worms etc, but I've also been reading the same product to my snail tank and the water in that tank hasn't exceeded a pH of 7. I may have messed up the baking soda measurements in the community fish tank.
<Yes; this is a more/most likely scenario>
Although unlikely that's the only possibility that I can think of. Since discontinuing the MelaFix I am at a standstill with my one symptomatic Danio.
<I really don't think this spot is pathogenic... NOT caused by a biological disease agent. DO READ on WWM re general Barb/Danio/Rasbora disease; the FAQs file/s>
I trust your judgment but really don't want to lost him. He was one of my first in that tank about 9 months ago. He's still happy and healthy as of now(minus the red spot), so I still have plenty of hope. I don't know if its relevant, but 2 of my albino cories have taken on a rather pale tone while the others still look shiny/iridescent. Thanks in advance! Danielle
<Read on! And write back if anything is unclear, incomplete in your mind re a course of action. Bob Fenner>

Cherry Barb With Potential Swim Bladder Problem.      11/18/14
Dear Crew,
I believe one of my barbs (male) has the above complaint. I noticed yesterday that he seemed to be having a 'private party', and was hanging in the water (mid to upper mid level of tank) at an angle - head facing down
around 35 + degrees.
<Mmm; what do you feed? Oh, I see this below>
So far, I have attempted to feed him with frozen peas (minus the shells), and some dried bloodworm.
<Cut this last... implicated in problems>

I've also heard that Epsom salt (magnesium sulphate?) should be added?
<Yes; possibly a good idea
; and not much potential downside. Read Neale's work on WWM re>
I've also heard that live daphnia or bloodworm would be best?
<Depends on cause. IF you use flake food, DO stop this>
Parameters :
ammonia 0
nitrite 0
nitrate (around 50)
<Zoinks! THIS is trouble...
NEEDS to be under 20 ppm. SEE WWM RE and fix>
GH 6
KH 10
pH 7.6
I have recently switched over to the Salifert testing kits, and it's surprising how much more accurate they are.
<Ah yes>
The API test suggested I had nitrates of around 10 - 25 (maybe 20 at a push), where as my new kit says otherwise. Maybe I need some more plants.
Water changes are two 10 - 15% changes per week, and I have also switched from Aquacare's water conditioner to SeaChem's 'prime' instead.
<Much better>
Please could you advise me further. :)
<Uhh, simply search, read on WWM Re>
Many thanks.
Kind Regards,
<And you, Bob Fenner>

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