Phytoplankton Culture Foaming

[Grady’s_Reef]

I recently started culturing phyto for my reef and split one of the cultures into 2 after about 4 days. Shortly after the new splits started to produce a foam unlike the initial culture. Is this caused by contamination in the culture?

The 2 on the left are the new split cultures and the right is one of the 2 initial culture vessels I started with.

Everything was sanitized with hydrogen peroxide. The only thing I can think of is the water I used had sat for 4 days and could’ve been contaminated with bacteria or something.

Any ideas on what might have caused this or tips on how to culture would be much appreciated!

 

[taricha]

foaming could go either way. Maybe it's like you said, the foaming is a contaminant or sign of some undesirable growth in the new cultures, or maybe it's the other way. Foaming decreased in the older cultures because the foam-able compounds got broken down by bacteria over time - this also occurs.