r/mealworms

what's wrong with them? I have a normal set up just oats, cardboard, no mites, 74F, I barely feed them but when I do they don't eat only some. ( I can't get pictures because I'm on a trip rn and forgot to ask this question before I went)

I use whole oat and bran I mix those

I feed them carrot and potato 3 4 times a week

I only keep the beetle because I can't hatch any eggs

I keep them in my basement

And I can't see any eggs hatch Im keeping them about 2.5 months and no eggs what so ever

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Putting mealworms in the fridge mimics the cold-season diapause they’d go through in the wild. It slows them right down so they don't pupate into beetles. The trick is to leave them alone, keep things dry, and never turn the whole box into a moisture trap.

This is for the fridge only — never the freezer.

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What you need

· A ventilated tub — a plastic container with lots of small holes in the lid, or a lid replaced partly with mesh. Airflow matters.

· Dry bedding / food — plain wheat bran, rolled oats, or rice bran. A layer about 2–4 cm (an inch or so) is plenty.

· For a frost‑free fridge ONLY: a damp paper towel, wrung out hard so it’s just moist, never dripping. This stops the fridge from slowly freeze-drying your worms. You also need a tiny cup or bottle cap to keep the towel off the bedding.

· A small spoon or scoop — for grabbing a portion quickly without taking the box out.

· If your fridge builds frost (an old-school direct‑cool model), you don’t need the damp paper towel at all.

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Setting it up (do this once)

1. Sieve any new mealworms to get rid of old frass and the odd dead one.

2. Put the worms and dry bedding into the ventilated tub. Don’t go deeper than about 5 cm of worms.

3. If your fridge is frost‑free:

   · Dampen a paper towel, squeeze every last drip out of it.

   · Put it into a small open cup or bottle cap — something that sits in the corner of the tub without touching the bedding. You can also tape the damp towel to the inside of the lid. It just has to breathe into the air, not sit on the bran.

   · If your fridge is the frosty type that builds ice: do nothing. Dry bedding only. No damp towel, no vegetables, nothing.

4. Snap the lid on and place the tub in the crisper drawer or a door shelf. Write the date on it. Now leave it alone.

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Feeding from the fridge (the only time you open the box)

· Never take the whole tub out to warm up. That creates condensation inside the lid, and the damp kills worms fast.

· Open the fridge, open the tub, quickly scoop out just the number of worms you need, then close it up and put it right back in. Be quick — that’s what stops condensation.

· The worms you’ve taken out will be cold and still.

· If your pet needs active, wiggly prey: tip them into a small cup and leave them at room temperature for a few hours until they start moving normally.

· If your pet doesn’t care: just wait a couple of minutes until they aren’t ice-cold, and feed.

· Never put uneaten worms back in the fridge. Once they’ve properly woken up, re-chilling them kills them. Only take what you’ll use.

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Looking after the humidity (frost‑free fridges only)

In a frost‑free fridge, the fan constantly pulls moisture out of the air. The damp paper towel will dry out over time. You need to keep an eye on it.

· How often? Depends on your fridge — it might be every few days or once a week.

· To check, open the fridge and quickly open the tub while it stays on the shelf. Glance at the towel. If it’s dry, swap it for a freshly dampened, wrung‑out one right there inside the fridge. Don’t carry the tub out to the kitchen counter.

· If your worms start to look a bit shrivelled or the bedding gets dusty‑dry, the air is too dry. Dampen the towel a tiny bit more next time, but never let it drip.

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Rules that actually matter

· No carrots, no potato, no fruit, no veg, ever. They rot in the cold and mould will kill the whole lot.

· Damp paper towel must never touch the bedding. If it sits on the bran, you’ll get mould. Always isolate it in its own little cup or tape it to the lid.

· In a frost‑building fridge, add zero moisture. The dry setup is enough. Adding anything wet will cause condensation and rot.

· No weekly “take it all out and check” routine. Warming them up, sifting, and re‑chilling stresses them and causes more deaths than it prevents. Leave the tub in the cold and only open it to feed or to quickly re‑wet the towel.

· Frost‑free fridges are not ideal for storing mealworms long term. If you have the choice, use an old‑school fridge that builds frost. If you must use frost‑free, the little isolated damp towel and regular quick checks are the only way to stop them from drying out.

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How long will they last?

Kept like this, with minimal disturbance and the right humidity (or no humidity in a frosty fridge), mealworms stay fresh and dormant for 4–8 weeks. You just open, scoop, and feed. The colony stays undisturbed in its cold, quiet, simulated winter — exactly how they’d survive in nature.

I originally got the meal worms for a baby bird i had to take care of until finding a rehaber[it was a cowbird] i had them left iver and my coworker has chickens so i offered to breed them and give him meal worms! Win win because im a massive bio nerd and i love my critters. I keep them in a plastic tub, the bedding is a mix of their original bedding and organic cornmeal i used in a pinch. I only have 28 worms, lost two sadly, im also raising earthworms alongside the mealworms(they are happy and laying egg sacs). I have 14 pupa's and today i just got my first beetle!!! I wanted to share it hear and if anyone has tips for beginners i would love that! I feed them fresh fruit and veggie scraps switch them out weekly sometimes two weeks, i have egg carton pieces they love to hide in, and i keep them in 70-75°F. (Photo of first beetle named ted buggy, in a tiny container)

For context to the why im farming them: i will be freezing them at high temp to make sure its humane and they will be given to other life forms(chickens :3) to help save my coworker alittle money. And ive- become very attached to the worms😭

I've had this project for about 3 years. I've got some free time now so I want to test the results.

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I created a mealworm sieve generator using a python library for the 2D files and a python script in blender for the 3D.

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The sieve generator has these parameters:

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Length

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Width

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Material Thickness

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Slot Width

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Number of Slots Per Row

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Rows

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Inner Padding

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Stackable

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In the Google drive there is a document detailing this better. There is an example sieve and it's parameters can be found in the document.

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https://drive.google.com/drive/folders/1iQf8bU2egSYujybtz4x1rjCpSUYltXBu

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If anyone would like I can generate a custom one.

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The slot width allows the sieves to sort mealworms by width.

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