Do you know why microalgae grown in ammonium medium supplemented with CO2 suddenly die after growing very well?

I need to cultivate Chlamydomonas reinhardtii in an ammonium media with Air + CO2 3% bubbling. After growing very well, my cultures suddenly bleach and die. I do not have this problem with nitrate...

13 February 2014 3,214 41 View