Disease Identification (with pics)

PygmyPepperJulli

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hi, new member so apologies if this email doesn’t follow protocol (and sorry for the terrible grammar I‘m in a rush)

I came home from a trip yesterday (5 days), having asked my grandad (with very clear instructions) to feed 1 tablet and turn off the light 3 days in so they wouldn’t starve (I’m overly cautious). Came back and one of my fish (neon tetra) cannot swim properly (swims at a diagonal or sideways angle, probably a problem with its swim bladder). I tried to net but it swam behind all my plants. When I finally netted it later, it had several black spots I didn’t notice before. put in a large glass container (I don’t have a quarantine tank) and it doesn’t seem to be getting better or worse. I’ve pretty much given up on it, however I need to know whether it’s contagious, as I am very worried about my other fish in the tank. It is still very active when I go near the container, however most of the time it lies sideways on the bottom (not moving, but still breathing).

None of my other fish have symptoms yet (thankfully) but one of them is missing? (A neon, I’m really really hoping it’s just hiding behind the plants as well and not sick/was sick and has now been nibbled)


Problems-
can’t swim properly
Black spots (bruises? Black cysts? Fungal infection? No clue)
Very red on underside of head and a little red in gills (but I’m pretty sure it’s not ammonia poisoning)
I actually don’t have any medication whatsoever (I don’t earn much money) so if there is any other treatment that I can do myself, please suggest

Tank description-
Heavily planted 10gal cube with neons and several types of corydoras (see username) (yes, it is overstocked, unfortunately, but I do 20-30% waterchanges with my gravel vac weekly or twice weekly abe it is heavily planted, so very clean water)
Has a heater + sponge filter
no idea about nitrates, Nitrites and ammonia (no test kit, but see above comment, I am poor but careful)

sorry about the pics (I took it out of the water only for a few secs to get a clearer photo)

If anyone has any ideas, please feel free to share! (and sorry about the length of this email)
 

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20% water changes is not enough especially considering you are overstocked.

I recommend you do an immediate 75% water change which may help with your issue.

You need a test kit to test for ammonia, nitrite and nitrate. Or at minimum , bring a water sample to your local fish store and hemave them test it.

You need to be doing a large water change every 7 days… at least 50-60%. You also should rehome some of your fish if you are overstocked.
 
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Sounds like neon tetra disease too me, isolating the fish was smart as this disease is contagious, sadly, neon tetra disease has no cure, so keep any effected fish in your quarantine tank until they pass. Neon tetra disease is usually caused from poor water parameters, too avoid this happening to more fish I would buy test kits for ammonia, nitrite and nitrate so you can monitor your water parameters.
 
You may need to euthanise the affected fish to do the kind thing by him/her. As others have said, if you're overstocked you need to be doing much bigger and more regular water changes. You should potentially look into either rehoming some of your fish (you don't say exactly how many you have) or upgrading to a bigger tank, it will improve your fishes wellbeing and be less stress for you as will be easier to maintain and keep on top of.
 
Any chance of a video of the fish?
You can upload videos to YouTube or another video hosting website, then copy & paste the link here.
If you use a mobile phone to film the fish, hold the phone horizontally (landscape mode) so the footage fills the entire screen and doesn't have black bars on the ends.

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It's not a common fish disease and the others are unlikely to get it. However, it could be from a parasitic worm that sometimes gets washed into waterways and ends up lost inside a fish. The worm doesn't spread to other fish because it needs a different host to reproduce.

The black holes are where the skin has split around the belly.

If the fish can't swim properly, I would euthanise it because it isn't going to improve.
 
I'm with Colin. I don't see a contagious disease, and it's probably coincidence that you were away. I'm not sure it's a parasite, but the little male neon is thin. It could also be in internal infection. I don't see a lot of grounds for hope.
 
Hi (and thanks for the replies)

1. I usually do 30% water changes, (sorry when I said 20%’s earlier I did them in two batches because I am planning to do one tomorrow as well, so I didn’t want to do them all at once).
I try and avoid doing large water changes because I really don’t want all my bacteria to die.

2. I am thinking about re-homing my fish, but I’m finding it really hard because I’m attached to them and I don’t know anyone with a tank that I would trust not to kill them (the reason I have too many in the first place is someone at the lfs who seemed to know what he was talking about convinced my dad to buy and extra 5 fish for my tank, even though I didn’t need them).
I was already aware that my tank is overstocked when I sent the original post, which is why I put it in the post. It hasn’t caused me any issues in the past, however I understand that I shouldn’t have this many.

sorry

3. I am pretty sure it isn’t NTD, however I was very afraid of that or something similar, which is why I quarantined it. It doesn’t have cysts, a curved spine and it seemed to be schooling with the others before I attempted to net it

4. I will do a large water change as per request, however I think at most I’ll do 50-60%, and a 40% at most weekly (I know you are the experts, but I’m on tank water and can’t afford to use that much weekly, combined with my fear of losing beneficial bacteria

5. I am saving up for a test kit at the moment, but for now I’ll just try to take it to the fish shop as soon as possible (I can’t drive, so I’ll need someone to take me)

6. My stock is (I already know it’s overstocked, but it’s also heavily planted, which removes much of the ammonia/nitrites/nitrates (I can’t remember which))

-3 Pygmy corydoras (I know all the cories should be in schools of 6, but long story short they aren’t and are happy all schooling together or going their seperate ways)
-3 pepper cories
-2 julii cories
-9 neon tetras (one is infected, which makes 10)

7. I haven’t euthanised it yet, as it doesn’t seem to be getting worse and I really din’t want to kill it if it’s getting better.

8. So, other than neon tetra disease, which I don’t think it is, does anyone think this think could be contagious? I am thinking, as none of the other fish in the tank seem to be affected, that the black spotting is bruising caused by some sort of physical trauma (bullying, although I have never seen that behaviour in my tank, or maybe getting stuck in the filter), which may have also injured it’s swim bladder, which is why it is swimming funny.

sorry about the long post and thanks for all your advice! (I may seem like a really annoying or inexperienced fish keeper, and it’s true I don’t have as much knowledge as any of you, but I am trying my best and have done quite a bit of research. and also sorry of this post is rude or really badly written it’s a bit late where I live ;))

also sorry I didn’t see you could add photos, or I would have added them earlier. As you can see it has several black spots and red gills (not ammonia poisoning I’m pretty sure) as well as swimming funny, and the red in its tail has faded a bit since these pics (not a cyst, just loss of colour). No secondary infections (fin rot, bloating, ich etc) so far.
 

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Also, isn’t neon tetra disease (and many other diseases) only present in new fish or from consuming an infected fish? This is why I was thinking it was trauma, but it’s really hard to know because I‘d been on holidays.

And also, sorry that there is 2 threads for this, I created one but something went wrong and I thought it deleted itself, so I created a second one and now there’s 2. If the other one could be deleted that would be great.
 
Ok… thanks guys (different advice from the other thread which I posted by accident, but I definitely think it’s a distinct possibility… :()

i was hoping it might be a physical trauma, however it seems much more likely that it’s an infection/parasite….

Thank you so much for you input!
 
Hi (and thanks for the replies)

1. I usually do 30% water changes, (sorry when I said 20%’s earlier I did them in two batches because I am planning to do one tomorrow as well, so I didn’t want to do them all at once).
I try and avoid doing large water changes because I really don’t want all my bacteria to die.

2. I am thinking about re-homing my fish, but I’m finding it really hard because I’m attached to them and I don’t know anyone with a tank that I would trust not to kill them (the reason I have too many in the first place is someone at the lfs who seemed to know what he was talking about convinced my dad to buy and extra 5 fish for my tank, even though I didn’t need them).
I was already aware that my tank is overstocked when I sent the original post, which is why I put it in the post. It hasn’t caused me any issues in the past, however I understand that I shouldn’t have this many.

sorry

3. I am pretty sure it isn’t NTD, however I was very afraid of that or something similar, which is why I quarantined it. It doesn’t have cysts, a curved spine and it seemed to be schooling with the others before I attempted to net it

4. I will do a large water change as per request, however I think at most I’ll do 50-60%, and a 40% at most weekly (I know you are the experts, but I’m on tank water and can’t afford to use that much weekly, combined with my fear of losing beneficial bacteria

5. I am saving up for a test kit at the moment, but for now I’ll just try to take it to the fish shop as soon as possible (I can’t drive, so I’ll need someone to take me)

6. My stock is (I already know it’s overstocked, but it’s also heavily planted, which removes much of the ammonia/nitrites/nitrates (I can’t remember which))

-3 Pygmy corydoras (I know all the cories should be in schools of 6, but long story short they aren’t and are happy all schooling together or going their seperate ways)
-3 pepper cories
-2 julii cories
-9 neon tetras (one is infected, which makes 10)

7. I haven’t euthanised it yet, as it doesn’t seem to be getting worse and I really din’t want to kill it if it’s getting better.

8. So, other than neon tetra disease, which I don’t think it is, does anyone think this think could be contagious? I am thinking, as none of the other fish in the tank seem to be affected, that the black spotting is bruising caused by some sort of physical trauma (bullying, although I have never seen that behaviour in my tank, or maybe getting stuck in the filter), which may have also injured it’s swim bladder, which is why it is swimming funny.

sorry about the long post and thanks for all your advice! (I may seem like a really annoying or inexperienced fish keeper, and it’s true I don’t have as much knowledge as any of you, but I am trying my best and have done quite a bit of research. and also sorry of this post is rude or really badly written it’s a bit late where I live ;))

also sorry I didn’t see you could add photos, or I would have added them earlier. As you can see it has several black spots and red gills (not ammonia poisoning I’m pretty sure) as well as swimming funny, and the red in its tail has faded a bit since these pics (not a cyst, just loss of colour). No secondary infections (fin rot, bloating, ich etc) so far.
You won't lose beneficial bacteria from doing large water changes, the bacteria lives in your filter and on other surfaces. With an overstocked tank you really do need to be doing at least 70% a couple/three times a week to keep on top of things and to keep the tank clean which will help your fish. I killed a lot of fish through a poorly maintained overstocked tank before I really understood where I was going wrong, it stresses your fish out and is likely to make them more susceptible to illness/early death.

You've got advice from some very knowledgeable members on here (not me, I'm still learning!) about the symptoms and the kindest thing to do for your tetra, I understand its not a nice thing to have to do but it's part of fishkeeping and the only alternative is leaving your fish to suffer. You can buy clove oil to euthanise the fish humanely if he doesn't improve soon.
 
Neion tetras ddisease is a microsporidia infection with Pleistophora hyphessobryconis. It is by no means limited to that species. One of the most common fish used in research is the zebra danio. They can definately get this disease and there are plent yof studies on it using zebras,

Now I am not saying this is what the fish in the thread has. The disease attacks the muscles of the fish. But, "The importance of microsporidia in captive fishes continues to increase with the continued dramatic increase in finfish aquaculture. Most microsporidia of fish are transmitted without intermediate hosts, and hence, cultured fish are particularly susceptible to microsporidian infections due to high stocking densities, compared to their wild counterparts." from--> Microsporidia in Fish
 
Beneficial bacteria doesn't really live in the water, except just by coincidence. It lives in the filter and on other surfaces in the aquarium. Water changes, therefore, won't hurt your BB. With this stocking in this small of a tank, you really should be doing big water changes. As long as you treat for chlorine and equalize the temperature, it won't hurt a thing. :)

Sorry for your sick fish. I don't know what's wrong with it, but you were right to remove it.
 
As already mentioned, beneficial bacteria don't live in the water. Most of us here do 50% or more when we're doing our water changes. The fresher and cleaner the water, the happier and healthier the fish 👍🏻
 
again, thank you so much for all the advice!

I’ll try and do 50% waterchanges each week (thanks for the info about the bacteria, I knew most of it lived on surfaces but also though some lived in the water) thanks to your advice, but I probably can’t do any more than that as we (QLD) are going into drought and our house is on tank water (I’ll try my best, even it means collecting the water while my shower warms up…)

sorry my replies on this thread are all mixed up and in a weird order, I got a bit confused

If it is parasitic as has been suggested-

1. Is there anything I can do for the fish without euthanising it? If it’s not contagious, can I put it back in the tank or in a plastic bag in the tank (so it doesn’t share the same water) so it can feel the heater? (I’m scared it will die in quarantine from lack of heater and filter and general space, but also terrified that if I put it back in the tank the other fish will be infected. Is that how it works with parasites? I’ve never dealt with them before. I would rather lose this fish and the others live than infecting the whole tank)
I ask if I have to euthanise it because this morning it seems to be a bit better, and while swimming sideways a bit, he seems too be more healthy and active. He’s still not eating though.

2. Where would the parasite have come from? Water changes?(Now I’m scared I might encounter it agin in the future). I did add some snails in recently… (slaps head and really regrets not quarantining the snails).

3. My tank water always seems to be really clean and clear, and I have done water tests at a life before (not recently, and I understand it may have changed) which came out really good, so I’m not sure why the levels would have changed so suddenly :(. I’ll see how I go with my fish in the future, but if I can’t rehome them, I’ll have to take them back to the store. I don’t have any other tanks, unfortunately.

4. I have dealt with suspected NTD (a not nice experience) at the very beginning of last year, and the symptoms were very different, which is why I was pretty certain it wasn’t NTD. Thanks for the info though.

5. I’ll try and post a vid

Thank you guys for all the info and have a good morning/night (whoever you live!)

Edit- thanks whoever merged the posts ;) (that’s why some of the comments are in a weird order)
 
OK, I understand the drought situation, and that makes water changes difficult. Do the best you can.

Clear and clean-looking tank water can still have ammonia, nitrites, nitrates. Tannin-stained, brown or yellow water can be extremely clean. You really can't tell by looking at it. There are all sorts of reasons that the levels can change.
 

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