At the start of my culturing using Joshs media cultures always did well, the last few months ill get maybe 1 of 3 cultures molding after the first few days. What can I do to stop this? I just ordered another batch of media and brewers yeast as well, that was for both flies and to use in a viv for the seeded cultures.. I need help here. Dont wanna go into the winter with too many molding cultures!

If you're using pre-made cultures, I'd probably add 50/50 vinegar water solution to the mix when you make them, instead just adding water. Either the mold inhibitor didn't get mixed correctly or not enough of it was added to the mix. You may want to contact Josh or whoever you bought it from. I'm sure they will appreciate the feedback, so they can either mix better or increase the amount of mold inhibitor they add.

Okay will do. Thanks marty! I tried making the cultures with a little less media and a little more water. Its not runny but its definately a less thick consistency. Think this will help?

I have had mold pop up in cultured media that was too dry. In the winter and summer I add more water to the mix and the problem has not shown up again since.

^this is most likely the problem. Make sure you are using 2/3 cup (boiling) water to 1/2 cup of media. Our media is a lot more dense than other media requiring more water.

Also, can you describe the "mold"? Got any pictures?

Green/blue molds pop up when it dries out on the top of the media. White is usually a sign of too much yeast.

How are you keeping the cultures? Are you culturing Hydei or Melanogaster?