Live blackworms & leeches? other critters?

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fishorama

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Jun 28, 2006
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I recently bought an ounce of live blackworms as a treat for my fish. I've read they can come with other critters like leeches but had never seen them before today. I kept them in a cottage cheese container in the fridge & rinse in dechlorinated water every day or 2. After several days there were 2 "other" animals on the side of the dish., oval or slightly tear drop shaped, maybe 1/8 x 1/16 inch or so. I know I've read about leeches & "possible" issues so I removed & squished them (a bit icky)...but maybe they'd be ok to feed?

I used to feel that way about "detritus" worms, chubby short red worms that show up in tanks' substrate or filters on occasion. Some fish eat them, it's no big deal right? But last time I saw 1 I fed it to my angels...& the "lucky 1" died a week or so later. Now these angels came to me as stunted adults but, was it coincidence? It's abdomen looked red...bacteria or worm? I can't dissect my fish but I did wonder. Many fish have some sort of teeth, either front of mouth or back farther (pharengeal?)...

What about other so called "harmless" critters like copepods, amphipods etc. I always thought they were just part of some tanks fauna although I've never noticed any in my tanks. Same thing, some fish eat them, nice live natural food.

I belong to an aquatic plant club so I often get plants from other people. I give them a quick tap water rinse, pick off any dead leaves, snails or eggs I see & done.

I also believe tubifex worms, even freeze dried, can harbor disease & haven't used them in almost 40 years. Frozen bloodworms, great, except I a tiny bit allergic to them. I just wash my hands after.

I'm feeling a bit grossed out just when I was comfortable grabbing a clump of wiggly blackworms & holding for my fish or slowing releasing them for my loaches.

So what does anyone else think or have experienced?
 

Narwhal72

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The leeches you see are blackworm leeches and they feed exclusively on the blood of blackworms. IME fish won't eat them. I generally try and remove them when I see them but if they do get in the tank I don't worry about it. Most die off in a few days to a week and on the rare occasion when they are surviving (because I feed a lot of blackworms in that tank) I just stop feeding blackworms for a month or two and they die off.

They don't harm fish at all. I breed cory cats in tanks with them.

Andy
 

FreshyFresh

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My only issue with feeding live goods is they are always going to have the potential to introduce some other live critter, parasite, etc, into the tank that your fish haven't battled before. They won't necessarily win the battle having lived their life in a nice maintained cube of water.
 

fishorama

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Thanks Andy, good to know! Makes me feel better.

Joel, I don't usually obsess with QT except for most new fish. Plants, meh...but I don't get potted 1s often, it's been years really. But there is a lfs that has had different critters (scuds etc) in their tanks. I might QT or at least pick all media & soak in tap water for several days.

I'm still a bit creeped out, lol, but now I can finish feeding the blackworms.
 

chenning

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I've seen them and they are harmless. No worries and the BLK Worms are great for the fish
 

OrionGirl

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I've had leeches survive without blackworms. Perhaps it's a different species, as they seemed to be detrivores. Gross, but nothing horrific. I never worried about them, and my larger mouthed fish would readily eat them if the leeches were on the glass.
 

fishorama

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Me too, lol! I wash w/antibacterial soap after feeding mystery live foods. Now do you see why I was concerned about your mosquito larvae feeding, lol? Eww, you never know!
 

ProjectMaro

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Lol, I hear ya. I will be paying close attention now. I have never seen any larvae get past 30 seconds before being ate. Quite a feeding frenzy.
 
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