No. Used this product to hatch and raise shrimp succesfully. 

Hi nnrreyram, Good day! Tough to say exactly how long you would need to use the isolation tank, because we don’t know how long it has been pregnant. Mollies can be pregnant for around 60 - 70 days. Thanks,

Yes it good one

The Imagitarium Aquarium Net Breeder is perfect for raising and protecting baby Mollies, Guppies, etc. I have used mine many times always with good results. Tho I do have a question, you wrote "mom is vary protective"....who exactly is she protecting her babies from? In my experience I have only witnessed the need to protect the babies being eaten FROM ALL other adult fish in the tank "the mom" included. Never have I seen a mom molly show any maternal instincts toward their young. What you see maybe just her trying to "catch" a snack?

Be careful with eggs in a mesh container. other fish may nip at them. I use an "egg bubbler" safer and takes up less space.

I know this is old.. first step is to click the walls into the holes on the bottom frame(flat square with mesh bottom). Gotta make sure it clicks put pressure on it until it does. The top frame then needs to be clicked in . There are two circle holes facing on the the outside of the bottom and top frame.. The clear tubes go in the back side. Insert a blue plug into each tube. Push the clear tubs through the circle holes in the bottom frame. Next there is a plastic that has your suction cup on it. Slip that on the clear tubes. Then push the clear tubes through the circle holes on the top frame. Insert two more blue plugs into the clear tubes. The plants click in on the blue plastic pieces with 4 nubs poking out. On the inside of the net you will see on the frame a raises edge that the blue plastic pieces will slide on.