Tilapia eggs don't hatch

[Hank Sullivan]

Fairly new to aquaponics.  A couple of times now, the fry never hatch out of the eggs and after about a week, the mother just spits them out. Finally I have to gather the egss and throw them out.

As soon as I saw that the mother was with eggs in her mouth, I dipped her out and placed her into 20 gal tank dedicated for raising fry.  I've done this before with no problem.  But this is the second time the eggs did not hatch.

Any ideas what might be going wrong?

[Justin Schaeffer]

It sounds like they didn't get fertilized. Maybe a male is shooting blanks.

[Dr. George B. Brooks, Jr.]

If you would ever like to try incubating the eggs after thy are fertilized, here is a paper that describes an easy technique.

Link to paper: http://bit.ly/ZESh8I

Note, the paper mentions a hemispherical egg incubation chamber. Here is what it looks like. Enjoy.

[Hank Sullivan]

Thanks for the responses.  I will look forward to reading the article, Dr. Brooks.