Flashing

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marnold00

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i have an issue in that one of my cherry barbs is flashing occasionally, but does it a lot after feeding.

The usual stuff:
Tank 18 US gal with a fluval U2 filter only ive removed the carbon and stuffed plenty of filter floss in its place
Temp 25 deg. Centigrade
Ammonia, nitrite nil
Nitrate usually around 20 by the time of water change
Weekly 25% water changes with RO water with minerals which have been exactly the same for the past 8 months

Inhabitants: 5 cherry barbs (i know its not enough but thats another story), 6 sterbai cories and 2 assassin snails.

Ok storytime. The tank has been running for 8 months
2-3 2weeks ago i had a couple of cherry barbs die which i did not see coming. I thought id check my pH and it was over 8 (source is 7.2 after leaving to stand for 24 hours with an air stone in it). Turns out i have had some limestone in the tank since day 1.. Oops.. So i removed that rock. Steadily seeing my pH lower with every water change.

7 days ago i added an XL indian almond leaF to my tank and i plan on continuing to use IALs.

About 5 days ago i started seeing a few cherry barbs flash so i started worrying. I bought some fluke solve which i havent used yet. I did a massive water change and now they seem much happier - i think my issue is that i was still feeding them as if i had 7 adult cherry barbs rather than 5, so i saw an increase in nitrates.

4 of the 5 havent flashed over the past 2 days. One of the cherry barbs still flashes numerous times in short succession but only after i feed them. Theres no clamped fins, appetite is as big as ever, and theyre all still behaving like the barbs they are... No signs of lethargy..

If i didnt have my cories id have just begun a 2 weeks treatment of fluke solve, but id rather not do it unless i really have to.

What would you guys do? Im going to do 3 50% water changes over the course of the week. Is flashing after feeding a thing?
 
I've never heard of "flashing after feeding" Especially if it's just one fish, did the fluke Medicine just cure for flukes, it's possible for the one fish that's still flashing to have a different illness, maybe internal parasites. Remove the fish that's still flashing at once, it's better to play it safe and monitor your fish and parameters for a few weeks to make sure everything's Ok, I'm thinking it has an internal parasite everything else seems stable
 
The fluke medicine is basically just praziquantel buffered with non medicinal ingrediants that they keep a secret as it isnt patented. Basically what us in the UK have to use rather than prazi pro. Im in a sticky situation of not having a hospital tank at the moment :/ so hes gonna have to stay. The thing is he doesnt show any other symptoms.

Its very frustrating. The meds shouldnt harm the cories but i dont really want to risk it just because cories are rather sensitive. I just have the pack there on standby for when i choose to do it. Ive been on the phone to the vet who designed the product to decide the best way to use it. Basically a big water change and one dose, leave it as long as i can (probably 8 or 9 days) before the next water change and then dose again incase the parasite is an egg layer - it gets internal and external parasites and its meant to be very good. Within 24-48 hours any live parasites are killed off, just not any eggs.

Fish flash occasionally in the same way that we have to itch. But its just bizarre that it only appears when im feeding. I may try different foods to see if its the flake causing it. I know some fish sometimes get bits of food stuck in their gills which can cause them to flash, so maybe there was nitrate burn because of the overfeeding, and if theres damage from that he could get irritated?

As i say hes got zero other symptoms and if anything is the most spectacular of the cherry barbs. And is still easily keeping his place at the top of the ranks in their little shoal
 
hmm.. this is odd indeed, my cardinal tetra has been going brought the exact same behavior as what your cherry barb, though she has calmed down with the flashing she still does it occasionally, I would dose the tank with meds if nescacary, I've been dosing my tank with ich treatment and my Pygmy cories and peppered Cory are fine, they are sensitive but can take Medications
 
Please don't take this the wrong way...but it is not wise to dose tanks containing fish with medications unless you are absolutely certain of the issue and the medication is the best to deal with it.

Cories are highly sensitive to all chemicals and all medications. So are characins. Some fish like cherry barbs may be less sensitive (though this is subjective) but it is still important to be careful. Every substance added to the tank water gets inside all the fish, by osmosis through the cells or at the gills. These substances enter the bloodstream and get into internal organs. The fish does not have to turn belly up to be detrimentally affected.
Ich remedies that contain copper are much worse for sensitive fish than salt and heat.

Flashing can be a sign of several problems, from water conditions (ammonia, nitrite, nitrate, pH, chlorine) to internal protozoan to external parasites. Clean water is sometimes all that is necessary, meaning major water changes using nothing but a good conditioner.

Edit (occurred to me subsequently): Removing a fish that is flashing is not usually a good idea, unless you again know what is causing it and this will help. Flashing caused by water conditions will obviously affect other fish too. And flashing caused by parasites or protozoan usually easily spreads to other fish. In any of these cases, netting the fish is going to cause it severe stress [netting a fish produces a "predator escape" physiological process in fish which is about as severe as stress can get] along with stress to other fish that get chased around or that will read the chemical fear signals being emitted by the fish being chased. And then there is the stress of being in a new environment alone, having to deal with water differences, etc, etc. Hospitalizing sick fish is not usually advisable, but in some cases it is necessary and beneficial.

To marnold...something in the first post caught my attention. When you say nitrate is usually arouynd 20 by the time of the water change, do you mean it is lower after and rises? What is the number? Nitrate should remain constant at all times. Increase the volume of the water change should help keep nitrate stable.

Byron.
 
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Please don't take this the wrong way...but it is not wise to dose tanks containing fish with medications unless you are absolutely certain of the issue and the medication is the best to deal with it.

Cories are highly sensitive to all chemicals and all medications. So are characins. Some fish like cherry barbs may be less sensitive (though this is subjective) but it is still important to be careful. Every substance added to the tank water gets inside all the fish, by osmosis through the cells or at the gills. These substances enter the bloodstream and get into internal organs. The fish does not have to turn belly up to be detrimentally affected.
Ich remedies that contain copper are much worse for sensitive fish than salt and heat.

Flashing can be a sign of several problems, from water conditions (ammonia, nitrite, nitrate, pH, chlorine) to internal protozoan to external parasites. Clean water is sometimes all that is necessary, meaning major water changes using nothing but a good conditioner.

Edit (occurred to me subsequently): Removing a fish that is flashing is not usually a good idea, unless you again know what is causing it and this will help. Flashing caused by water conditions will obviously affect other fish too. And flashing caused by parasites or protozoan usually easily spreads to other fish. In any of these cases, netting the fish is going to cause it severe stress [netting a fish produces a "predator escape" physiological process in fish which is about as severe as stress can get] along with stress to other fish that get chased around or that will read the chemical fear signals being emitted by the fish being chased. And then there is the stress of being in a new environment alone, having to deal with water differences, etc, etc. Hospitalizing sick fish is not usually advisable, but in some cases it is necessary and beneficial.

To marnold...something in the first post caught my attention. When you say nitrate is usually arouynd 20 by the time of the water change, do you mean it is lower after and rises? What is the number? Nitrate should remain constant at all times. Increase the volume of the water change should help keep nitrate stable.

Byron.

Byron thanks for that. Very helpful. Im glad my concerns about meds arent over the top.

Iexcuse my ignorance about nitrates, but if i do 30% water change then surely the nitrates will drop by 30%? Providing nil in the source water ofcourse. It wouldnt surprise me if my nitrates have been going up these past few weeks as im sure i have been overfeeding.

With regards to the nitrate figure ive provided thats only because ive recently only tested just before a water change, although i shouldve said my last nitrate test was a few weeks ago. Current numbers are pointless because i did a couple of large water changes this weekend.

Its probably a stress related illness... Too high nitrates, pH being lowered (abd probably the hardness too?), less fish than an ideal scenario in the shoal.. All in all im fairly sure thats a recipe for some unhappy fish :(

Im only going to medicate the tank if the others all start flashing. For now ill continue with large water changes throughout this week :)

Ill also use Seachem Prime. Please dont bite my head off for this but i havent actually been using water conditioner as ive been using 100% RO - maybe naivety but i thought i dont see the point in adding chemicals to remove chlorine, heavy metals etc when there are none. I didnt realise the likes of Prime could help with other stuff too. Ive been doing that for the past 8 months (im not overly experienced with fish) so maybe that is something i could change as my reseaech is showing that conditioners like prime help to reduce stress levels

hmm.. this is odd indeed, my cardinal tetra has been going brought the exact same behavior as what your cherry barb, though she has calmed down with the flashing she still does it occasionally, I would dose the tank with meds if nescacary, I've been dosing my tank with ich treatment and my Pygmy cories and peppered Cory are fine, they are sensitive but can take Medications

Tyler i dont really wish to dose a tank containing cories based off one fish - especially when that one fish has zero other symptoms. It is bizarre behaviour though. Ill keep you updated with whether the water changes help
 
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Quick update. Thankfully my tank is near the tv so i watch it a lot (source of the paranoia maybe?) But basically seen 2 flashes today from the aforementioned barb (2 hours watching maximum).

I dont feed them on mondays and tuesdays they get pea :p #fishydetox

One other barb flashed 3 times in quick succession, but all on the same side and not overly violently, so most likely an actual itch/dislodging algae.

If it was flukes i would have expected an effected fish to flash consistently every few minutes? Or have i misunderstood the symptoms of flukes? Id have thought theyd show realy discomfort and flashing all the time. Especially as its been 5 days since it started - i wouldve thought thered be far more symtpoms.

Note the cories arent visibly effected but i know its uncommon for them to be affected by such ailments
 
Murphys law that id post such an update. The new flashing fish is still flashing intermittently, and ive seen another one do it once.


pH is 7.5, nitrites and ammonia nil, nitrates look to be <20 (i find that test particularly hard to read using the api master test kit)

Im thinking water change and dose... The thing is they do it a few times over the course of 5 mins or so and then they stop...
 
Some comments on issues mentioned.

Ill also use Seachem Prime. Please dont bite my head off for this but i havent actually been using water conditioner as ive been using 100% RO - maybe naivety but i thought i dont see the point in adding chemicals to remove chlorine, heavy metals etc when there are none. I didnt realise the likes of Prime could help with other stuff too. Ive been doing that for the past 8 months (im not overly experienced with fish) so maybe that is something i could change as my reseaech is showing that conditioners like prime help to reduce stress levels

Prime is not going to do anything of significance to alleviate stress, at least not here. The claims made by most if not all manufacturers of water conditioners that they replenish slime coats and alleviate stress are mainly misleading.

As for a conditioner, this is beneficial with treated water, but if you are using RO and then adding minerals I would not bother. All conditioners add TDS (total dissolved solids) and these can increase and impact fish (especially soft water species). Then there is the chemical(s) themselves, which get inside fish. When there is no need for the conditioner, this is best avoided.

Prime does detoxify nitrate, but this has limits. It is intended to detoxify nitrate in the source water. The detoxification is temporary, 24-36 hours according to Seachem, then the nitrate again becomes "nitrate" no longer detoxified. Prime is intended to deal with ammonia, nitrite and nitrate when these are present in the source water. It is also beneficial in new tanks to aid in the cycling, if fish are present, but there needs to be daily or alternate day water changes using Prime. We are not dealing with any of these conditions here.

Im only going to medicate the tank if the others all start flashing. For now ill continue with large water changes throughout this week

Again, you need to pin down the cause. Medications for gill flukes for example will have no benefit if the issue is say internal protozoan, or water problems. And adding the gill fluke medication will further stress all the fish, making things even worse. I would do some good water changes and avoid stressing the fish as much as possible.

Iexcuse my ignorance about nitrates, but if i do 30% water change then surely the nitrates will drop by 30%? Providing nil in the source water ofcourse. It wouldnt surprise me if my nitrates have been going up these past few weeks as im sure i have been overfeeding.

With regards to the nitrate figure ive provided thats only because ive recently only tested just before a water change, although i shouldve said my last nitrate test was a few weeks ago. Current numbers are pointless because i did a couple of large water changes this weekend.

Its probably a stress related illness... Too high nitrates, pH being lowered (abd probably the hardness too?), less fish than an ideal scenario in the shoal.. All in all im fairly sure thats a recipe for some unhappy fish

Stress is the direct cause of 95% of fish disease in an aquarium. So it is always wise to keep stress as low as we can.

To the nitrates...if nitrate is rising in the aquarium, there is a reason that must be eliminated. Too many fish (size and numbers here), overfeeding, insufficient water changes, decaying organics (substrate, filters) can all contribute. Organics can be difficult to control sometimes. I have this in one of eight tanks, and after two years the cause is still a mystery. Anyway, you want to keep nitrate steady, and as low as possible. If nitrate is under 20 ppm, and remains stable for months, you're fine. If it is say 10 ppm one day, and 20 ppm within a couple days, and this is repetitive, there is something you need to fix. I would increase the volume of your water changes, vacuum into the substrate during these, and keep the filter well rinsed. The brown gunk that accumulates in the filter is organics, and you want to keep this as clear/clean as possible.

Byron.
 
Quick update. Thankfully my tank is near the tv so i watch it a lot (source of the paranoia maybe?) But basically seen 2 flashes today from the aforementioned barb (2 hours watching maximum).

I dont feed them on mondays and tuesdays they get pea :p #fishydetox

One other barb flashed 3 times in quick succession, but all on the same side and not overly violently, so most likely an actual itch/dislodging algae.

If it was flukes i would have expected an effected fish to flash consistently every few minutes? Or have i misunderstood the symptoms of flukes? Id have thought theyd show realy discomfort and flashing all the time. Especially as its been 5 days since it started - i wouldve thought thered be far more symtpoms.

Note the cories arent visibly effected but i know its uncommon for them to be affected by such ailments

I just posted in length further to your previous post, and you added this info during.

Cories, being substrate fish, actually tend to be more susceptible to flukes and parasites (ich, etc) because they are near the bottom. Flukes will show red gills, and with the gill cover held out from the fish making the gills more easily seen. I had this once, brought in on some cories.

There is also the possibility of an internal protozoan, and there will be no sign of this except flashing. Metronidazole added to the food is the best treatment for this. Metro will not harm the fish (unlike external treatments like medications in the water), it is an antibiotic. It works wonders on protozoan. Antibiotics can become less effective if over used, same as with humans, so you don't want to overdo it, but aside from this is it harmless to most fish. Personally I would want to see more evidence before using metro.

I am going out on a limb here, but from your description I would be more inclined to see this as ich. There are many very knowledgeable scientific folks in the hobby who believe ich is always present, and it takes severe stress to cause a break-out we see (the spots). There is really no other explanation if for example ich suddenly breaks out after a major stress event (like a heater fail) when nothing new has gone into the tank in months if not years. Flashing is the first sign of ich, because the parasite first attacks the gills and we can't see it but the flashing is the external sign it is there. Keep the water changes adequate (50-60% once a week), avoid stress. I have had this disappear with new fish in QT without any medications.

Byron.
 
Byron thank you so much. Your description of a slight case of ich sounds more likely i guess. Although since my last post there is more flashing :( but no lethargy etc and inbetween flashing they are themselves.

Correct me if im wrong but your general consensus seems to be good, large water changes and hold tight.

I know common ich treatments are salt and higher temp. Salt is going nowhere near my tank because of cories. Is it worth raising the temperature now, or is that a measure for only if the dreaded whitespots appear?

Im not going to med the tank or anything for the time being. I cant really see how i could tell if theres parasites. They are eating normally and i havent seen long stringy faeces. Id guess when it comes to fish, only medicate if you can see an obvious symptom. Until that point if its ambiguous (ie. Flashing) just keep the water changes good.
 
Byron thank you so much. Your description of a slight case of ich sounds more likely i guess. Although since my last post there is more flashing :( but no lethargy etc and inbetween flashing they are themselves.

Correct me if im wrong but your general consensus seems to be good, large water changes and hold tight.

I know common ich treatments are salt and higher temp. Salt is going nowhere near my tank because of cories. Is it worth raising the temperature now, or is that a measure for only if the dreaded whitespots appear?

Im not going to med the tank or anything for the time being. I cant really see how i could tell if theres parasites. They are eating normally and i havent seen long stringy faeces. Id guess when it comes to fish, only medicate if you can see an obvious symptom. Until that point if its ambiguous (ie. Flashing) just keep the water changes good.

At the moment, yes, I would do a good water change and clean the substrate well, the ich "cysts" can lie there, but nothing beyond that except for monitoring.

If ich is deemed the issue, salt and heat are the best remedies. I too used to nay-say salt with my cories, loaches and characins, but Dr. Neale Monks advised me that salt was far less detrimental than copper (common ingredient in ich remedies) and chemicals, and given his expertise I used salt with the temp raised to 86F/30C. Salt was 2 grams per liter. I used this in my 70g which has 50 wild caught cories, and not one sign of discomfort. That was a year ago, the fish are still with me, and spawning like mad. I recovered another two tiny fry out of the canister filter when I gave it its 6-week cleaning last week. About three months back, I saw one cory flash a few times, then nothing, and last week, same. Based upon what Neale told me, the ich is likely still present, but the fish are basically immune and if healthy can fight it off. Course, the flash could have been anything, a bit of food stuck in the gills maybe.

Heat is not well received by cories either, or many other fish, so I went up to 30C/86F on Neale's advice as max, along with the salt. But only if it seems more likely ich (or velvet which can be much the same) is the culprit and it worsens.

I have even had new fish in QT and noticed a couple spots, but no treatment other than major water changes, and the spots fell off, flashing stopped completely, and after six weeks the fish went into the display tanks. A stress-free environment, and good water, works wonders. Which after all is not much different than humans is it?

Byron.
 
At the moment, yes, I would do a good water change and clean the substrate well, the ich "cysts" can lie there, but nothing beyond that except for monitoring.

If ich is deemed the issue, salt and heat are the best remedies. I too used to nay-say salt with my cories, loaches and characins, but Dr. Neale Monks advised me that salt was far less detrimental than copper (common ingredient in ich remedies) and chemicals, and given his expertise I used salt with the temp raised to 86F/30C. Salt was 2 grams per liter. I used this in my 70g which has 50 wild caught cories, and not one sign of discomfort. That was a year ago, the fish are still with me, and spawning like mad. I recovered another two tiny fry out of the canister filter when I gave it its 6-week cleaning last week. About three months back, I saw one cory flash a few times, then nothing, and last week, same. Based upon what Neale told me, the ich is likely still present, but the fish are basically immune and if healthy can fight it off. Course, the flash could have been anything, a bit of food stuck in the gills maybe.

Heat is not well received by cories either, or many other fish, so I went up to 30C/86F on Neale's advice as max, along with the salt. But only if it seems more likely ich (or velvet which can be much the same) is the culprit and it worsens.

I have even had new fish in QT and noticed a couple spots, but no treatment other than major water changes, and the spots fell off, flashing stopped completely, and after six weeks the fish went into the display tanks. A stress-free environment, and good water, works wonders. Which after all is not much different than humans is it?

Byron.

Thank you. Very informative - i guess youre correct in your comparison. If we get ill, a bit of rest and relaxation and eating healthy is normally always enough.

With regards to the substrate cleaning, i have quite fine sand as a substrate, so i tend to swirl the siphon to lift as much visible crud off the substrate as possible. Does this seem reasonable? I know i wont be able to see any spores with the naked eye... I cant think of any other way to do it without sucking up lots of sand.

Ill buy a second heater tomorrow (always good to have a backup anyway) and then if the white spots appear ill turn the heat up to 30 and if after a week its no better ill leave it like that and add some salt based off your measurements. Is table salt ok? Id have thought aquarium salt is just an expensive table salt...

Im fortunate in a way that my cories are sterbai so they should be able to handle the heat better than any other cory.
 
Thank you. Very informative - i guess youre correct in your comparison. If we get ill, a bit of rest and relaxation and eating healthy is normally always enough.

With regards to the substrate cleaning, i have quite fine sand as a substrate, so i tend to swirl the siphon to lift as much visible crud off the substrate as possible. Does this seem reasonable? I know i wont be able to see any spores with the naked eye... I cant think of any other way to do it without sucking up lots of sand.

Ill buy a second heater tomorrow (always good to have a backup anyway) and then if the white spots appear ill turn the heat up to 30 and if after a week its no better ill leave it like that and add some salt based off your measurements. Is table salt ok? Id have thought aquarium salt is just an expensive table salt...

Im fortunate in a way that my cories are sterbai so they should be able to handle the heat better than any other cory.

Yes, Corydoras sterbai is very tolerant of warmer water,often used with discus for that reason.

I run the end of the water changer over the top of the sand, sort of stirring it up a tad, and I have found that if you're careful the sand won't come all the way up.

Table salt is not good for fish. It may contain iodine and other substances to prevent caking, etc. Sea salt will work (according to Neale), but you can buy Aquarium Salt which is very inexpensive. API make one, I used this one. Keep it well sealed, as it can absorb moisture and this can affect it. Don't use Marine salt or Rift Lake Cichlid salts as these contains minerals you do not want.
 
Yes, Corydoras sterbai is very tolerant of warmer water,often used with discus for that reason.

I run the end of the water changer over the top of the sand, sort of stirring it up a tad, and I have found that if you're careful the sand won't come all the way up.

Table salt is not good for fish. It may contain iodine and other substances to prevent caking, etc. Sea salt will work (according to Neale), but you can buy Aquarium Salt which is very inexpensive. API make one, I used this one. Keep it well sealed, as it can absorb moisture and this can affect it. Don't use Marine salt or Rift Lake Cichlid salts as these contains minerals you do not want.

One last question before i leave you in peace. Say by the weekend it is no better/it is worse and i decide to go down the salt and high temp line, do i just put the full quantity of salt in with the water change or do i gradually add it over the course of 48 hours? I could imagine all in one go could discomfort the fish - the same way some people 'burn' if they go in a particularly salty ocean...

Thank you for the fast, well informed and coherent responses. These fish dont half worry me! By keeping them in a tank which is by no means close to their natural habitat i worry about them so much. When we keep them happy they reward us with attention and by looking great...
 

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