I have been keeping Grindal worms for about 6 months.
I use the nylon scourer method and have 4 small containers on the go.
I am using 2 nylon scourers in each container with dog pellets as food.
I keep the scourers moist but there is no water visible in the container.
Once or twice a week I pour 1 cup of water into each container and then drain and replace it with fresh water.
A month or so ago while doing the change I poured the old water into a tall glass container.
As always the waste water from the containers is cloudy and looks unpleasant.. Unintentionally, I didn’t immediately dump this waste and it stood overnight.
The next afternoon there was 10mm of brown sludge on the bottom of the jar and the top was slightly murky. When I held the glass container in front of a strong light I could see movement in the water. Using a strong magnifying glass I was surprised to see this water was teeming with what we generically call infusoria..
I lack the facilities to identify individuals, but what I guess to be Paramecia seemed to be the predominant occupant of the very crowded water. I also think there may be some rotifers or other different infusorians as well.
Since that time I have found the infusoria every time I rinse the Grindals. Obviously after washing they go into the fry tank.
I am wondering if anyone else has come across this, or have I just had a Eureka moment?