Black worms murdered half my Betta collection!! :(

On Monday, I went to get my usual portion of live bloodworms at the pet store, but was told: we're out of bloodworms, but we have blackworms! They're bigger than the bloodworms, but the fish usually chew them up!

Now it's Thursday, and I've lost five of my precious Bettas (so far) and Rhaegar looks like he's not going to make it, either.

I knew I had heard something about blackworms being bad for Bettas at some point, but I couldn't remember why. Some sleuthing led me to the information that blackworms can live in Bettas' stomachs and eat/thrash their way through the fish from the inside!

So, please don't feed your Bettas more than one or two live blackworms at a time.

Rest in Peace, Little Red, Zoolander, Little Blue, Pineapple, and Daenerys. And please hang in there, my buddy Rhaegar! <3

RIP Daenerys




RIP Little Blue




RIP Pineapple



RIP Zoolander



Please hang in there, Rhaegar <3

 

OH, I am so sorry this is happening to you, how horrible, those pet store people should be ashamed! They just killed five bettas!

 

Jeez! What a terrible outcome! Did the pet store know you were going to give them to Bettas? If so you should complain! If they don't know what they're talking about, they shouldn't be offering up advice!!!

 

I really do like and trust my friends at this particular local pet store, so I will tell them what happened, but I think the issue was not in the worms themselves, but in the number I allowed my Bettas to eat in one feeding (they're hard to grab with my large feeding tongs, so I was putting in as small of a squirming ball of worms as I could grab, but not counting out one or two worms at a time).

This is the information I found online (I have not read this book, so please excuse me if it is incorrect!):

Bettas may engorge on black worms, resulting in gastric distress and sometimes death. Many aquarists cut them into pieces with a razor blade before feeding them to bettas. Black worms that survive partial ingestion can tear the stomachs of small fish, killing them.
(The Betta Handbook, pg. 93, Goldstein)

I have since put the rest of the offending worms around the roots of my background plants, in the hopes that they will burrow into the substrate and become good little detrivores for my tank ecosystem, and only an occasional single-worm-at-a-time snack for my Alien Bettas, who seem to feed more sensibly than my ravenous B. splendens!

I will let you all know if Rhaegar pulls through... Keep your fingers crossed for his recovery! <3

 

Dang! sorrry! I would consider going to the store and telling them what what happened polity. At least they will know, maybe they can try to prevent others from buying them for bettas.

 

Dang! sorrry! I would consider going to the store and telling them what what happened polity. At least they will know, maybe they can try to prevent others from buying them for bettas.

Yes, that's exactly what I plan to do - everyone at that store LOVES seeing my pics and videos of the Betta tanks, so I am sure they will be concerned and let others know not to overfeed blackworms to small fish in the future!

 

I don't even like bettas generally, but zoolander was a stunner!

 

Aww that completely sucks. I’m so sorry you’ve lost so many fish in one go. As above I’m not a huge betta lover but they were stunning fish, I’m genuinely sorry you’ve lost them.

Could it be not so much the black worms but something they’ve carried in with them ? Or is it genuinely they’ve gorged themselves ? Either way it’s good that you’ve made a post to warn others.
Hang in there Rhaegar !

 

Could it be not so much the black worms but something they’ve carried in with them ?

I was thinking the same. Similar cases are known from people feeding red mosquito larvae (bloodworms) to malawi cichlids, dwarf cichlids, wild bettas and gourami. People thought for a while it was because they have barbs and hooks, which turned out not to be true, as it also happened when being fed deader than dead, i.e. frozen.

It is probably a combination of very bad nutritional value, bad production conditions (contaminated water) and probably an allergen.

Blackworms are also a candidate for being bred in bad quality water, containing pathogens and parasites.

I would take at least two of the deceased fish and let a vet do an examination. If they really have ripped gastro-intestinal tracts theory confirmed. If not, there's likely a pathogen at work.

 

I don't even like bettas generally, but zoolander was a stunner!

Right? Dang that was a good looking fish. Could he turn left?

 

I was thinking the same. Similar cases are known from people feeding red mosquito larvae (bloodworms) to malawi cichlids, dwarf cichlids, wild bettas and gourami. People thought for a while it was because they have barbs and hooks, which turned out not to be true, as it also happened when being fed deader than dead, i.e. frozen.

It is probably a combination of very bad nutritional value, bad production conditions (contaminated water) and probably an allergen.

Blackworms are also a candidate for being bred in bad quality water, containing pathogens and parasites.

I would take at least two of the deceased fish and let a vet do an examination. If they really have ripped gastro-intestinal tracts theory confirmed. If not, there's likely a pathogen at work.

That's a really good idea. I was thinking it was the gorging, because I fed all 25 of my Bettas these same blackworms, and only 5 of them seemed to perish quite suddenly after looking haggard for a day or two... I will save the bodies I have not yet frozen and bring them in for an autopsy ASAP. Thanks for the suggestion!

 

Take along some of the worms too for pathogen or contamination analysis.

 

Good Idea, Good luck!

 

When I search online, I don't find any vets that mention fish, only state offices that deal with aquaculture. How widely available is this serve - checking fish for cause of death?

 

When I search online, I don't find any vets that mention fish, only state offices that deal with aquaculture. How widely available is this serve - checking fish for cause of death?

I live in Germany. We have few vets that take in fish, but those that do usually send them in to a qualified lab. And in a case like this when somebody has lots of fish (presumably breeding?) the expenses are worth it.
Guess that's the problem for most cases, it's not worth it for a single fish. In this case it could be vital for the remaining fish if it was a pathogen. So it's advisable.
Going by the prices here I'd presume it costs around 300 bucks.

 

Not sure of location, but Seattle area I could get recommendations if needed. Wife runs a clinic whose sister location sees exotics. They don’t see fish, but I know that Brad knows people that do, it’s his circle lol

 

I know someone that took down their tank when they couldn't figure out the constant fish death. He would probly have paid $300 to figure out what was wrong.

 

I know someone that took down their tank when they couldn't figure out the constant fish death. He would probly have paid $300 to figure out what was wrong.

Frankly, in most cases of "mysterious" deaths, especially if recurring, it's 99% a bad and contaminated source selling bad quality sick fish. Plus nowerdays weak genetics in massproduced species can lower the life expectancy of many species to less than a year.

The money is actually only invested cleverly if there is stock (expensive/rare species, a whole collection or a breeding operation) to save or prevent losses.
Otherwise the results are usually useless, as often the treatment isn't cheap either and if you have "standard" species you can get for a 5er a piece it really isn't going to cut it.

 

So sorry this happened.

I feed live black worms all the time to my small fish. Scarlet Badis, Chilis, Ember tetras, Peacock Gudgeons. I have never had a fish die from eating them.

Although bettas are big pigs and would eat all 10 worms if you put 10 in there, I dont see how that many fish would have died all at once. Im guessing bad worms also.

Did you rinse them every day? Or at least every other? I keep mine in the fridge and rinse them. Maybe the worms were loaded with ammonia? IDK just throwing out things. If that could even happen.

 

Poor little Daenerys' corpse has been sent to the UC Davis labs for a necropsy to determine cause of death and (hopefully) point to something I can treat, if it is indeed a pathogen carried by the blackworms. To be continued...

So sorry this happened.

I feed live black worms all the time to my small fish. Scarlet Badis, Chilis, Ember tetras, Peacock Gudgeons. I have never had a fish die from eating them.

Although bettas are big pigs and would eat all 10 worms if you put 10 in there, I dont see how that many fish would have died all at once. Im guessing bad worms also.

Did you rinse them every day? Or at least every other? I keep mine in the fridge and rinse them. Maybe the worms were loaded with ammonia? IDK just throwing out things. If that could even happen.

Yes, I keep my blackworms in freshly changed water from my little outdoor Betta girl "pond" daily. All of the fish were very healthy before being fed the blackworms, and in all different tanks, so the food is the only thing I can think of that they all had in common... I'm anxious to see what the lab results say!

Take along some of the worms too for pathogen or contamination analysis.

Alas, they don't accept worms at the lab - only ornamental and food species!

I live in Germany. We have few vets that take in fish, but those that do usually send them in to a qualified lab. And in a case like this when somebody has lots of fish (presumably breeding?) the expenses are worth it.
Guess that's the problem for most cases, it's not worth it for a single fish. In this case it could be vital for the remaining fish if it was a pathogen. So it's advisable.
Going by the prices here I'd presume it costs around 300 bucks.

Yes, my exotic veterinarians all recommended sending the carcasses to the UC Davis labs here in California, which charge $135 to process up to 3 aquarium fish no more than 10" in length (plus overnight shipping, and any subsequent lab testing fees).

Since all of my Bettas are indeed fancy imports meant for breeding and show, it is important to know what caused these deaths so I can treat the rest of the collection, if indeed the cause of death is something that can be treated or avoided in the future.

 

StarGirl and anyone feeding these live worms.
They are stored in a bucket placed in a sink with the tap running a little fresh unconditioned water continuously 24/7 in shops in Australia .

As i mentioned to you in a previous post the water in a live culture I had got pretty gross in just a few days. I am thinking you should be rinsing a lot more often? Even in the refrigerator?

I am suggesting the store you brought them from was not storing the worms in a satisfactory manner?