Rosy Minnows

[Tom Highum]

I was wondering if anyone knows how to breed / keep rosy minnows for feeding.

[BJnMe]

BREEDING: This is the interesting part, many people think these fish merely scatter their eggs around, this is not true, and their breeding is far more complex. To induce spawning all you really have to do is provide a 16 hour photo-period with 8 hours of darkness, this with a good diet of things like bloodworms, brine shrimp and daphnia is all it really takes. When ready to breed the males will develop a spongy pad around their head (hence the name fathead) with breeding tubercles on top. These tubercles look like small white bumps or pimples. He will also turn dark in color, almost completely black. The male will then stake out a territory. He will defend the cave and try to attract a female with the use of pheromones. He will also dance in a figure eight pattern. Once a female decides she wants to spawn with him he will lead her into the cave where they will spawn on the roof of the cave. Sometimes more than one female will spawn with a male. The male will care for the eggs, rubbing them with his spongy nape and snout in order to keep them clean. Spawning usually occurs in the morning.

THE EGGS AND FRY: What you choose to do with these is up to you, chances are the success rate will be higher is you move the eggs to another tank and place them next to an air stone. You can also keep them with the male but remove the others and remove him after they hatch. The young can be fed Artemia nauplii, Hikari first bites (or other baby fish food) and finely ground flakes.

Breeding the Fathead minnow (rosy red) - MonsterFishKeepers.com

[Tom Highum]

how big of a tank should they be kept in? Caves?

[BJnMe]

From another site How to raise Rosy Reds, Pimephales promelas, with pictures

In the Aquarium. Our basic setup for breeding this fish in the lab was a 10-gallon aquarium with an under gravel filter. We used 4-inch-long sections of 4-inch diameter PVC pipe for the egglaying sites, two per tank. A new clay flowerpot laid on its side or a slate cave would work as well.
Lighting. Two males and four females went into each breeding tank. Photoperiod (duration of lighting) was 15 hours per day. Temperature was 72 to 74 degrees.
Egg Harvesting. At peak breeding, I was removing one or both tubing sections with eggs weekly and replacing them with fresh ones. The ones with eggs were placed in separate aquaria with aeration and treated with a fungus preventive.
Parental Care. It wouldn’t have mattered to the fry whether they hatched in Papa’s presence or not. Once free-swimming, the fry are ignored by the parents, so long as those parents are kept well-fed.
Increased Eggs. We merely removed the eggs to increase egg production. Once Papa is done with previous responsibilities, he’s ready to go again. Females seem to be egg machines. If the eggs aren’t removed, Papa will clean and protect them until they hatch.

[Tom Highum]

Sexing and fungus preventative?

[whiteroses91]

If you want something easy, do guppies! Toss a couple in a tank and watch them multiply! I started out with a dozen or so guppies and now have hundreds. I have so many, I sell them on my aquarium forum. Pretty much all you have to do is have a clean, stable environment and they'll do the rest.