Suggestions (including salt?) to prevent blackworm culture crashes?

[memorywrangler]

I've had a couple of seemingly healthy black worm cultures crash on me.  I finally got some new ones and I'm trying to prevent another crash.  I have some theories and some questions (at the bottom)

I think my setup is pretty good:  room temperature,  2.5gallons with a sponge filter, and daily 10% water changes.  The water parameters are consistently good. (The photo is my temporary quarantine/leach removal container)

I have two theories for the cause of the crashes:  Leaches and parasites.

Leaches

The basis for the leach theory is that with the last crash, the worms vanished and I was left with lots and lots of leaches (which came in with the black worms originally).  Then, I left the culture alone without changing anything.  In a few weeks the leaches were all gone.  I surmise that the leaches starved to death in the absence of the worms. 

So, I'm thoroughly picking through the worms to remove leaches.

Parasites

The parasite theory comes from this passage in a research paper I found (Lumbriculus is the genus black worms belong to):

"Ectoparasites can sometimes be associated with Lumbriculus obtained commercially or from natural habitats; their levels can get to a point where survival of the worms is jeopardized and the cultures crash. However, these ectoparasites can be removed by treating cultures with 0.6% sodium chloride in spring water. The EPA lab (Duluth, MN) found that salt provokes release of ectoparasites from the surface of the worms."

It's from here: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8667080/

There's no reference given the for EPA lab's finding, which is annoying.

Questions

1. Any other suggestions to prevent crashes?
2. Has anyone tried treating black worms with salt?
3. Any suggestions on what process to use?  (e.g., how long to treat them)

Thanks

 

Edited March 26 by memorywrangler

[CJs Aquatics]

im sorry to hear about the crash, I was hoping you might be willing to message me your set up/ perhaps sourcing information on how you have cultured them in the first place as it’s something I’m extremely interested in. I would rather hear from someone on the forum doing it with relative success then the internet videos that’s info varies drastically. I will also stay tuned to see if anyone offers the advice you seek so as to perhaps prevent a similar situation in the future, I’m not well enough versed in the worms to offer any myself but I’m super interested in this…

[memorywrangler]

I got them at my LFS.  I think they get them from here: https://aquaticfoods.com/BlackwormCareM.html, but I'm not certain and they say they are out of stock.  They have been out of stock at all the LFSs here in San Diego for several months.

My old setup was  plastic shoe-box container from home depot, with an overflow.  I had a tiny sponge filter, some guppy grass, and some cubes of coarse sponge filter material that the worms seem to like.

I dumped a quart of dechloronated water in each morning, and it would overflow into a bucket.

I fed them some leftover shrimp food I had around every few days.  

I'm not sure they grew that much, but they lived a long time until...they didn't (crash).

My new plan is to co-culture them with scuds and bladder snails in a 5 gallon.

 

 

[Guppysnail]

Towards the end of this thread @modified lung posted their final successful method including a thing for leech removal. Your setup is different but it may provide some ideas for you. 

 

[memorywrangler]

On 3/26/2023 at 2:16 PM, memorywrangler said:

Has anyone tried treating black worms with salt?

I did some experiments last night with a 0.6% salt solution. I left them in for 5, 10, and 20 minutes, rinse them in freshwater and let them sit overnight. In the morning everyone is still alive so I’m treating the whole batch with a 0.6% salt solution for 20 minutes.

I don’t know how I’m ever gonna tell if this was successful 🙂

Edited March 27 by memorywrangler

[Odd Duck]

On 3/27/2023 at 7:01 AM, Guppysnail said:

Towards the end of this thread @modified lung posted their final successful method including a thing for leech removal. Your setup is different but it may provide some ideas for you. 

 

Was it leach removal or Planaria removal?  I know he puts a piece of PVC pipe in the buckets because Planaria seem to collect on the PVC which he pulls out and cleans regularly (can’t remember if he said how often).  I know he said he cleans out the leaches and carefully inspects for them but don’t remember him stating a removal method?

As far as salt - I’ve never tried to treat with salt but if I could score a decent amount of worms I would try using salt on a small portion to see how they react.

If I could, I would arrange to have some Planaria and leaches in with the worms during the treatment and I would try it as a “dip” by maybe putting worms and all in a fine net so I could more easily pull them out and plunk them back in tank water.  I would watch all the various critters and see what they’re doing in response to the salt “dip”.  I know you can rinse blackworms briefly (30-60 seconds seems to be a common recommendation) in tap water while cleaning them and you do that at least daily to twice daily with apparently minimal risk to the worms.

We need @OnlyGenusCaps to chime in since he seems to have had the most success with actually growing his blackworms. I’ve been doing a version of his blackworm towers and not had any apparent significant growth but I started with small numbers of worms.

I managed to get some blackworms established months ago in one of my sand bottom tanks and have been sucking some up with a syringe with some tubing attached as they show above the sand at feeding time. They’re getting squirted into the tower a few worms at a time.  Their population certainly hasn’t gone gangbusters for me.  I’d really love to get a bigger population of them going.

[Guppysnail]

On 3/27/2023 at 6:44 PM, Odd Duck said:

Was it leach removal or Planaria removal

Both attached to the pipe I believe the last ones were wild collected. 

Edited March 27 by Guppysnail

[OnlyGenusCaps]

On 3/27/2023 at 5:44 PM, Odd Duck said:

I’ve been doing a version of his blackworm towers

Oh no, those are @modified lung's towers.  Not mine.  That was an ingenious system.  Can't be mine!  I just do mine in gravel in a sterlite container, with a sponge filter.  Super low key.

[memorywrangler]

On 3/27/2023 at 6:07 PM, OnlyGenusCaps said:

Oh no, those are @modified lung's towers.  Not mine.  That was an ingenious system.  Can't be mine!  I just do mine in gravel in a sterlite container, with a sponge filter.

I ended up combining sterilite and a couple variations on @modified lung’s towers:  one is part of a HOB inlet pre filter and the other is two nested hydroponic planters with gravel in between.  So far they seem to prefer the nested pots, but it’s only been 3 hours.

I also put some in with my scuds and bladder snails.

We’ll see how it goes!

[Odd Duck]

On 3/27/2023 at 8:07 PM, OnlyGenusCaps said:

Oh no, those are @modified lung's towers.  Not mine.  That was an ingenious system.  Can't be mine!  I just do mine in gravel in a sterlite container, with a sponge filter.  Super low key.

Oh, I knew that!  😆 🤦🏻‍♀️ 🤷🏻‍♀️ Old brain moment.  😂 

[modified lung]

On 3/26/2023 at 2:16 PM, memorywrangler said:

Leaches

I've seen leaches eating blackworms for sure. I have a crazy theory leaches might be important for fragmenting the worms—biting them in half—because I've seen some big population growth in a big tank full of mud, no gravel, and lots of leaches. 

On 3/26/2023 at 2:16 PM, memorywrangler said:

Ectoparasites can sometimes be associated with Lumbriculus obtained commercially or from natural habitats

Good find. I had no idea.

On 3/26/2023 at 2:16 PM, memorywrangler said:

Any other suggestions to prevent crashes?

Something I never see mentioned is how much slime or whatever it is that blackworms release into the water. The slime probably lowers the amount of oxygen the water can hold. It looks like they release even more slime when they're stressed which could be why they suddenly crash so fast and hard, especially if large population size in a small space (or maybe the increased oxygen needed by the growing population) is a stress factor.

On 3/27/2023 at 3:44 PM, Odd Duck said:

Was it leach removal or Planaria removal?

Both. The PVC is a secondary though. Leaches and planaria stick to surfaces and blackworms don't which is great. So I take my container of blackworm and dump them into a different container. Then I remove all the leaches and planaria sticking to the bottom and sides of the first container. I transfer them between containers every few hours until I stop finding more. I've never been able to remove them all this way so I add the PVC pipe to keep them more under control. Whenever I see a lot on the PVC, I just take it out and spray it down with the garden hose.

On 3/27/2023 at 7:02 PM, memorywrangler said:

the other is two nested hydroponic planters with gravel in between

Omg, that's brilliant. I'm going to do that.

Edited April 2 by modified lung

[memorywrangler]

I got another batch of black worms and did some more experiments with salt.

1. I tried leaving some worms in the 0.6% salt solution overnight, rather than just for 20 minutes.  Results:  They all died
2. I picked out the the leaches in this batch and treated them with 0.6% salt.  They seemed to die in a few minutes!

So, that suggests I could dispense with picking out the leaches and just treat with salt.

My only hesitation is that a bunch of the leaches were dead when I picked them out, so maybe the leaches were already sickly to start with.  I'll try it again with my next batch of worms and leaches.

Edited May 23 by memorywrangler

[memorywrangler]

I got another batch of worms and left the leaches and some of the worms in the 0.5% salt solution for 24 hours.  Neither the black worms nor the leaches died this time.

I give up...  I guess I'll keep picking leaches.

On the other hand, my black worm colony is doing well, so maybe the salt is helping to reduce crashes (of course, now I'm sure it'll crash this evening...).