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i just never seem to get it right ... wont gel right...dries out... contam... or will not susport growth.  i give up in agar 

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Won't gell correctly is usually caused by one of the following:

1) weight of agar to volume of water is incorrect
2) agar not fully disolved into water
3) not using distilled water
4) sterilization temperature not correct
5) sterilization time not correct
6) using low grade agar

Dries out:

1) pour thicker plates
2) seal petri after innoculation
3) not used soon enough
4) using low grade agar

Contam:

1) improve technique
2) use flow hood or glove box  (skip the oven tek!!)
3) add antibiotics to agar mix
4) add sterile hydrogen peroxide to agar mix (after sterilization)

Will not support growth:

1) agar has dried out
2) using low grade agar
3) not adding proper nutrients to agar
4) too high temperature during sterilization causing carmalization


Remember, agar with nothing else added has very little nutritional value for whatever you are growing to consume.  You need to add sugars and starches to get things to grow.. PDA for example is agar with dextrose and potato starch added.