Seriously? Any idea what they're doing wrong? Or are you talking about the crazy fancy guppies?

I got the plain ones, and if they're in a tank where they don't get eaten, they multiply like rabbits. There's a tank here that I put in some guppies for a razorback musk to chase after. It wasn't at all interested in the guppies, and now the tank is bordering on overstocked just from the guppies breeding.

You want to also make sure the filtration is not too crazy. A good sponge or UGF and plenty of plants and you will have mad babies which are a good source of free food. Insects are always good too.

It was fancy guppies. Some of them had other fish, some of them had just guppies. For some of them, I would guess that there may have been some stress on their females, because it seems it was while the female was pregnant or right after they have baby guppies, and for some of them there were more males than females. But for a large number, no explanation.

I had not thought of the filtration though. From now on, I'll start asking.

I am breeding mealworms. They're like the perfect pet. I haven't fed them since January, and I had them thrown in a box for the past 2 months (I had a week to pack and move after finals), and I have beetles, pupa, and mealworms.

I'm not even sure if filtration has much to do with it. The turtle tank they're going nuts in has a pretty heavy duty filter. As in if they get caught in the out flow.. whoosh!

I've never tried breeding mealworws. I usually just swipe a tub of 500 when I need 'em from my friends place. How are you doing it? What are you keeping them in and other questions.

It's super easy. If I can't kill them, anyone can do it.

You start off with a critter tote and about an inch or two of oatmeal flakes. Then throw in some mealworms. I went for large mealworms, and I think I put in 10 or 15. You add carrots for food and water. Do that as often as you need (But I forgot several times, and quite a few survived). After a couple weeks, you'll see them change from mealworm to the pupa stage. A few weeks later, you'll see beetles. A few weeks after that, you'll see baby mealies. I think, from what I read, it takes 10-12 weeks total to go from mealworms to beetles having babies.

Fridge or no fridge? I keep them in the fridge.

No fridge. They don't grow up in the fridge. It's their Neverland. So you can use that space for a drink or two.