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kendraschmidt_gw

Can worms compost shrimp shells?

KendraSchmidt
11 years ago

I'm new to vermicomposting, and I'd like to know if I can put shrimp shells (raw or boiled) into my compost bin, once I place my composting worms in the bin?

I've heard that it can only be veggies, etc, but I use shrimp a lot in my house and usually put the raw (or plain boiled) shells into my compost bin. Will I be unable to do this once the worms are in the compost bin?

Comments (16)

  • KendraSchmidt
    Original Author
    11 years ago

    Anyone? Please help! :o(

  • KendraSchmidt
    Original Author
    11 years ago

    Perfect, thank you Mendopete!

  • sbryce_gw
    11 years ago

    Just like egg shells? Worms don't eat egg shells. But if the shrimp shells break down in the compost pile, then they should be fine in the worm bin. It would not hurt to put a few in one corner of the bin and see how they do.

  • mendopete
    11 years ago

    I toss at least a dozen eggshells in my bin every week. I have free-range Rhode Island reds, and my worms LOVE their eggshells. I have seen them hanging out in a 1/2 shell. I don't know if they are eaten or just break down, but it is gone when I harvest VC. My garden loves my VC so it is all good!

    I have a couple of 8-9" abolone shells that have been cycling through my systems for about 3 years. The shells are bigger and thicker than oyster shells. Whenever I run into then at harvest they have a little worm colony living inside them. They are slowly breaking down and getting smaller.

    IMHO I believe if an item is compostable, worms will eat it eventually, if given the opportunity. Everything that was once alive is compostable. Moderation is the key.

  • dowbright
    11 years ago

    I've read for years that dried, crushed up egg shells are fantastic grit for worms. Just with a simple spoon I can get it very fine in less than a minute, for about two dozen eggs.

    The same would happen with time, but I like to speed things up. I don't see egg shell tiny bits when I harvest. Maybe they just turned brown, or maybe they did use them as grit! I doubt I'll ever know. But it's easier to put them in the bin than to walk all the way out to the compost! Especially in the drought/heat we've had this year. (subliminal global warming subliminal) ;)

  • PRO
    equinoxequinox
    11 years ago

    I let them air dry. Put them into a brown paper bag or newspaper. Roll over them with a wine bottle shaking the bag periodically. Do not breath dust.

  • 11otis
    11 years ago

    I regularly put shrimp shells (raw & cooked) in my compost bin that is populated w. worms but I do NOT put s.shells into my worm bin, mainly because of the smell. The worm bins are closer to the house and the compost bin is at the back of the back yard (closer to the neighbour's backyard, lol). Egg shells dissolve in acid and I gather so will shrimp shell & the like that contains calcium. So sprinkling eggshells every now and then in your worm bin is a good thing in reducing the acidity. I don't bother with litmus paper etc. to check. I just use my nose, and when I sort of smell a sour smell from the scraps, then add more ground egg shells.

    equinoxequinox: when you have finished using your oven for something, put your eggshells in w. the power OFF. You will find that it will be much easier to grind them after.
    I have an old baking sheet I use for this and a wine bottle (empty, lol) to roll it with.

  • HU-618682799
    5 years ago

    Can worms eat a little fish food. Like flake food?


  • armoured
    5 years ago

    Shrimp shells and egg shells are completely different - egg shells being almost entirely calcium carbonate, whereas shrimp shells are mainly chitin (basically a type of sugar polymer). Shrimp cells can be digested and broken down by various organisms. There may be useful amounts of calcium and possibly some 'grit' value to shrimp shells, but very different from egg shells. I've found the shells break down fairly readily in compost (but never bothered to figure out how long).

    My guess on the smell aspect is that the fishy smell is from other substances on the shell - and I find it goes away in compost fairly quickly. May be unpleasant in a worm bin, though.

  • Bud Wrangler
    5 years ago
    I’m not a vermicompost expert but I do know that what “Armoured” says is correct about the chitin in shrimp shells. I add crustacean shell meal and flour (I grind the crushed “meal” shells in a coffee grinder) to my soil mix, in part, for the chitin. I believe this will make it easier for the worms as well. I think adding whole shells to a worm bin would be asking a bit much of the worms; but, like I said, I’m not a worm expert. Yet! Lol!
  • pcreasy
    4 years ago

    I'm going to dehydrate my shrimp tails, then put them through the coffee grinder I keep for egg shells. I'm going to dehydrate carrot greens, too, and see if they're sturdy enough to be ground as well. I hear worms especially love their food processed like that (and it is said to include some charcoal, too). I'm new to this, too, so I'm happy to report some of my worms are gettin' mighty fat and sassy!

  • armoured
    4 years ago

    I think this grinding up of shrimp shells is unnecessary, although sure, it might help them breakdown a bit faster.

    The stuff they're mostly made of - chitin - is present in soil and nature all over the place, like the hard shells of insects. It's also widely present in fungi. You don't really find insect shells in places like soil. Or, ahem, in scats of other animals.

    In short, nature knows how to break them down without any extra work on our part. I've not tried to time how long, but I can't recall ever finding intact shrimp shells even when turning relatively 'young' piles, so it's my impression they actually break down pretty quickly.

    As for smelly/fishy smells, I just toss some part-done compost or leaf litter or sawdust on top, or you can bury a bit in your pile, that seems to deal with odours well.

    Again, may be a bit more sensitive in a worm pile (don't have worms right now), but my guess is shrimp shells would break down pretty quick without much effort, even if they seem tough to us.

  • napapen
    4 years ago

    I would hesitate to put shrimp shells in my compost because it is from an animal.



  • HighColdDesert
    4 years ago

    I've always thrown everything that comes out of the kitchen in the compost heap. Large bones and avocado pits and peach pits sometimes haven't broken down and have to go through again, or get tucked under the permanent mulch somewhere. I think it's fine to compost animal products, despite some advice I've seen online. I'm not sure, really, why there is such strong advice not to compost animal products. They break down.

  • armoured
    4 years ago

    @HighColdDesert, thank you. And I agree. There are some good reasons that often recommended not to compost animal products - but note that the shrimp shells (chitin) themselves are not an issue, only any 'stuff' still attached to them.

    The reasons usually noted are smell, tendency to attract pests like rodents (also a function of smell) and potentially disease vectors. But personally, I will compost any animal/meat/dairy/egg bits and have never had any problem; I just don't compost any large meat chunks and large bones or chunks of fat or grease and the like (to each their own - many do without problems). I certainly don't worry about any small bits; they are readily broken down in a pile. I'll toss dead birds in there as well, seen lots of posts from folks tossing in turkey carcases and the like in hot piles and they disappear too.

    The problems (exaggerated in my view) are pretty easily dealt with - first, the amount matters, I'm not composting dead steer or anything (although I read an article about this being done to dispose of carcasses - basically just a big pile of wood chips and the like). Smell - like any compost pile, cover with leaves or cardboard or finished compost or whatever and there should be no smell. Finally, either hot compost or let it compost longer (and basic hygiene with the final compost).

    I understand why they say keep animal bits out of a compost pile, and everyone should do what they're comfortable with (adjusting for their local conditions). But the 'no animal bits' is not an absolute rule, just a rule of thumb to make things easier/reduce problems.

    (Note this may not apply to worm bins, partly just because they're usually much smaller and indoors).

    Shrimp shells? Don't compost a ton of raw whole shrimp in your back yard, but shells left over after cooking/eating - not a problem at all in my experience.