900 M13a MEDIUM
| Peptone | 0.25 | g |
| Yeast extract | 0.25 | g |
| Glucose | 0.25 | g |
| Vitamin solution (see below) | 10.0 | ml |
| Modified Hutner's basal salts (see below) | 20.0 | ml |
| 0.1 M Tris-HCl buffer (pH 7.5) | 50.0 | ml |
| Artificial seawater | 500.0 | ml |
| Distilled water | 420.0 | ml |
| Vitamin B12 | 0.2 | mg |
| Biotin | 4.0 | mg |
| Thiamine·HCl·2H2O | 10.0 | mg |
| Calcium pantothenate | 10.0 | mg |
| Folic acid | 1.0 | mg |
| Riboflavin | 10.0 | mg |
| Nicotinamide | 10.0 | mg |
| p-Aminobenzoic acid | 10.0 | mg |
| Pyridoxine·HCl | 10.0 | mg |
| Distilled water | 1.0 | L |
| Nitrilotriacetic acid (NTA) | 10.0 | g |
| MgSO4·7H2O | 29.7 | g |
| CaCl2·2H2O | 3.335 | g |
| (NH4)6MoO24·4H2O | 9.25 | mg |
| FeSO4·7H2O | 99.0 | mg |
| Metals ''44'' (see Medium No. 149) | 50.0 | ml |
| Distilled water | 950.0 | ml |