When I wish to move fry as you describe, I move the entire cave with dan and fry in it. I submerge a 1 quart measuring cup, gently move the whole cave into it and then move it all to the new tank where I reverse the process.
I usually do this as close to fry kickout time as i can judge. Most times the fry will all be out of the cave in 24-48 hours and I then return dad and cave to its original spot in the breeder tank.
What makes the common person uncommon is common sense.
Put the cave in an angle over 45 degrees with opening down in a breeder, the male will not like it and leave the cave after a while you can easy remove the wigglers then by gently shaking he cave.
Greetings,
John
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