Phyto Culture - strange detritus above the water line?

[Deisler]

Hi,

I have been culturing phytoplankton (nanno) for a few weeks now and following strict sterilization steps. I have managed to harvest a few times already so all has been going well I think. I use f/2, dosage on the higher end. I use rigid airline with boiling bubble rate.

Today, a culture I split and started 4 days ago appears to have some detritus above the water/bubble line. See the picture I took below. The other bottle I started on the same day does not have anything like that.

This bottle has a little settling at the bottom but definitely not excessive. The culture color seems ok and is getting darker.

I've tried to search around and have not found any mention of detritus above the waterline... Anyone has seen this before? I'd like to understand if this is contamination or perhaps caused by other issues?

P.S. there is no similar detritus in the water that I can see.

Thanks a lot

 

[Rtaylor]

I wouldn’t worry about it, it could be from the fertilizer you’re using?