A Lab Notebook

 
Contaminated Cultures... Start Again!
Monday April 12

Both of my 20 liter cultures are in stationary phase. One of the cultures has become contaminated by a smaller species (coulter counter and visual observation). Additional evidence for contamination was the increased Fv/Fm of the suspended culture media in the contaminated culture. The non-contaminated culture had the expected low Fv/Fm of suspended media associated with stationary phase cultures which have mostly settled to the bottom.
I autoclaved enough of each of the f/2 solution ingredients to fill 2 new 20 liter culture vessels and begin again.
This contamination has set back my plans to innoculate a flume for a big experiment.
I filtered an resuspended the non-contaminated culture in 1 liter of media. I also took a sample of the uncontaminated culture and used it to innoculate another 1 liter culture. I am now growing 2 separate 1 liter cultures of S. costatum.
Hopefully there is a picture below of me working hard deploying a glider about 2 weeks ago.

Also, I ran at bear Mountain State Park in NY this weekend. There are a couple of small peaks near 1200 feet nestled along the banks of the Hudson (elevation ~ 100 feet). There are a few roads of varying length that one can take to get the 1000 foot elevation gain. I will be back this weekend to continue strength training.
- posted by alex @ 18:01