Earthworms / Nightcrawlers safe as fish food?
Sat, 04/03/2010 - 09:10
Does anyone have any inside knowledge about how commercial earthworms/nightcrawlers are cultivated? Specifically, are they given anything (exposed to pesticides, etc.) that may harm aquarium fish over the long term?
During a period of feeding difficulty with my Takifugu ocellatus puffer I decided to try some nightcrawlers from Petsmart, and then eventually from Walmart, since Petsmart could never keep them in stock. My concern being, the worms from Petsmart are probably fairly safe, however, those from Walmart, which are meant for fishing, may not be, since no one would ever really notice if they were killing fish in a pond/lake/river...
Thoughts? Experiences?
Sat, 04/03/2010 - 11:30
#2
Well, I have been trying it, for the last year with the ocellatus puffer...and he's not dead yet, so I guess that's a good sign. 
I also rinse them really well, but have read about people soaking them in vitamin water for three hours. The problem with that is, I think the majority of the reason the puffer eats them is because of their wriggling when they hit the brackish water...so soaking them might defeat the purpose.
I agree with your opinion though Samuel. I'd be surprised if they WEREN'T grown with some chemicals... I hope I'm wrong, but hence why the puffer only gets two or three worms a week, just to vary his diet and keep him interested.
Sat, 04/03/2010 - 14:12
#3
Hey Greg,
If you're worried about the worms injesting pesticedes etc before you feed them to your fish, I know that you can keep them for a while and feed them safe nutrient rich food until their system has been flushed of toxins. If you keep them in a covered tupperware container with damp paper towel for substrate and feed them a pretty quality cereal (maybe one high in protein for your puffers?) then you can control more exactly what you're feeding.
Sat, 04/03/2010 - 14:33
#4
That's a great idea Connor. Thanks for the input. I don't know a lot of worm physiology, therefore I just kept them in their container they came in, with the supplied dirt, and tried to use them quickly. I was scared off from experimenting with the worm's substrate and food when, a few weeks ago, I noticed their dirt looked a little dry, so I put some water in to moisten it. They promptly died and became moldy. 
Interestingly, although everyone fishes with worms, nobody but my big puffer seems interested in the worms. None of my large cichlids pay much attention to them, except maybe staring at them for a while, and the worms are too big for my littler fishes.
So, do I shred the paper towel, and crumble the cereal? Or just dampen whole paper towels and cereal and let them go at it? I'm assuming I want/need non-printed paper towels to prevent the ink from leaching out?
I've also had an interest in growing some California blackworms, since ALL my fish love them...except my African Leaf fish. Right now I pay about $40 for two pounds of blackworms shipped to me. It would be great if a few of us started growing some various foods (blackworms, ghost shrimp, nightcrawlers, etc) and trading amongst ourselves to save some money. I'd much rather give my money to locals than people I don't know. I'm fairly sure I spend more on fish food a month than I do for my own food....
greg
Sat, 04/03/2010 - 15:09
#5
Greg,
In all honesty I've never done any sort of project like this for aquarium purposes, I think it had something to do with a biology class a couple of years ago...But if I were going to grow worms on a large scale I would use those sliding plastic storage drawers (do they have a more specific name?) and have each individual drawer didicated to one type of worm. I think soil would be a better substrate than paper towels, but I don't know where you can buy soil that doesn't have all of the added fertilizers for plants. In any case, it's important to keep it damp and clean. I think crumbling the cereal and then dampening it a bit would be the best aproach.
Hope that helps,
Sat, 04/03/2010 - 21:26
#6
Thanks Connor. I have seen instructions for a compost pile/worm farm online, but being that only my puffer eats the earthworms, I probably wouldn't put the effort into it.
As for the black worms, I have also seen instructions in growing these, which looks pretty easy, but I'm not sure what kind of yield one would get without a large tank dedicated to it. Maybe one of those huge plastic bins from Walmart would work. The great thing I love about these worms is that they stay alive in the substrate (except in the brackish tank), and will eat detritus and multiply while providing grazing opportunities for the fish. I find them alive while vacuuming my gravel months after I have stopped feeding them. As matter of fact, my gold severum is picking up bunches of rocks now and spitting them out trying to get the worms....
Thanks for your input,
Greg
Hm, no experience. I wouldn't be surprised to find they had ferts and stuff added. I would at least rinse them really well. I'm not sure how you would even go about finding that out. If you try it, let us know how it works out.