if you want to keep some of the babies alive you need to get the smallest pvc pipe and aquarium safe silicone.
cut the pipes 4in long glue 4 together then lay another row going the opposite way. cut it just a little smaller. do this for four layers.
make a lot of them. put them in the tank at different angles. The babies will pick there holes.
The babies will eat each other and the mother will eat her babies.
my crayfish pool has loads of all size pvc houses stacked in it. I have hundreds of all size crayfish.
the crayfish pool is the actual filter for my lg. tropical fish pool.
The crayfish are the most important part of the filter system. As you can tell the crayfish breed them selves.