How to remove bacteriophage - (Nov/29/2005 )

Some of my collegues started to research on bacteriophages, and sometimes it ruins flasks.

After they finish the propagation of their phage, phage remained in some flasks even after autoclaving, and the people who use the same flasks fail to culture bacteria(the host of the phage). This doesn't happen all the time, but quite often. This is waste of flasks!!

How do you usually remove bacteriophage after use? Are there any commercial cleaners?

Thanks in advance.

Bleach?