I have a problem whist preparing NGM plates. The NGM solution...

Hi Fanglian,

Thank you for your help.

However, I should have provided more information in my first question.

We've been very careful with mixing solutions (time and tempareture). We use "Fisher Scientific" NaCl, "BD" Pepton and "Melford" Agar. We used to use "Formedium" Agar for many years but it caused cloudy NGM. So we switched to use "Melford" agar (as suggested by one of PI). To start with it was very clear and everyone's happy. But last few weeks, we noticed that NGM is cloudy again and it's before anything added. It is clear just out of autoclave but it becomes cloudy when it's ready for the additives.

Hope I explained better this time.

Kazuko

Hi, Kazuko,

The cloudy solution is very likely due to the formation of CaSO4. When you add CaCl2 or MgSO4 to the solution, you need to make sure that the solution is mixed well before adding the 2nd one.

Hope this helps.

Fanglian