Fry Pen

I don't know if it will work, but I built this today for my fry.

I used a 1-1/2" PVC frame which I filled with sand so that it will sink.  I then used Zip Ties to fasten this plastic fence material to both sides of the frame and filled it with short pieces of pipe.   The fry will now have a place to hide until they are large enough not to be eaten.