The water first turns cloudy, but clears up once the infusoria eat the bacteria that caused the cloudiness. At this point, the infusoria are ready, and usually are visible to the naked eye as small, white specks swimming in the container.

How long does it take to make infusoria?

So, as a responsible breeder, you will need to culture infusoria for your fish fry. You should do this 3–4 days before you expect the fry to hatch as it takes 3–4 days for the culture to really take off. For starters, you'll need some tank water.

How do you harvest infusoria?

The easiest way to harvest infusoria is to use an eye dropper or turkey baster to collect a small amount of water from the top of the culture jar and to squirt it directly into the fry tank.