Soil Extract + Sodium Metasilicate Medium

Modification of Soil Extract Medium for diatoms.

Directions

For 1 L Total

1. Prepare 1 L of Bristol Medium and thoroughly mix.
2. Discard 40 mL of the Bristol Medium.
3. Add 40 mL of previously prepared GR+ Medium [Note: The GR+ should be filtered to remove soil particles].
   • For 1.5% agar medium add 15 g of agar into the flask; do not mix.
4. Cover and autoclave medium.
5. When cooled, add filter sterilized sodium metasilicate.
   • For agar medium, add sodium metasilicate, mix, and dispense before agar solidifies.
6. Store at refrigerator temperature.