Reference: Stein, J (ED.) 1973. Handbook of Phycological methods. Culture methods and growth measurements. Cambridge University Press. 448 pp.
| Stock | Substance | Concentration | Amount added to medium (mL/L) |
|---|---|---|---|
| 1. | Na2SiO3•9H2O* | 5 g/L | 10 mL |
| 2. | Ca(NO3)2•4H2O | 57.56 g/L | 1 mL |
| 3. | K2HPO4 | 10 g/L | 1 mL |
| 4. | MgSO4•7H2O | 25 g/L | 1 mL |
| 5. | Na2CO3 | 20 g/L | 1 mL |
| 6. | f/2 vitamin solution | See below | 1 mL |
| 7. | Na2EDTA•2H2O | 1.00 g/L | 1 mL |
| 8. | Trace metal solution | See below | 1 mL |
| 9. | Ferric citrate | 6.00 g/L | 1 mL |
| Citric acid | 6.00 g/L | ||
| 10. | H2SeO3 | 0.163 g/L | 0.5 mL |
* Adjust pH of Na2SiO3.9H2O to neutral before adding to the media
If Ferric citrate and citric acid not available, substitute:
- FeCl3•6H2O (3.15 g/L) and Na2EDTA•2H2O (4.36 g/L). Add 1 mL/L to medium.
Trace metal solution
| Substance | Concentration (g/L) |
|---|---|
| 1. H3BO3 | 2.86 g |
| 2. MnCl2•4H2O | 1.81 g |
| 3. ZnSO4•7H2O | 0.222 g |
| 4. Na2MoO4•2H2O | 0.390 g |
| 5. CuSO4•5H2O | 0.079 g |
| 6. Co(NO3)2•6H2O | 0.0494 g |
Dissolve each of the above substances separately prior to adding the next.
Adjust pH of the final CHU-10 medium to 6.4 for diatoms and green algae or to 8.5 for cyanobacteria and Cladophora (for Cladophora, mix 50% of CHU-10 @ pH 8.5 with 50% filter-sterilized lake water).
f/2 vitamin solution
Substock solutions:
First prepare separate substock solutions of cyanocobalamin (Vitamin B12) and biotin in purified water (e.g., Milli-Q, Nanopure, distilled water).
| Substock | Substance | Concentration |
|---|---|---|
| 1. | Vitamin B12 (Cyanocobalamin) | 10 mg/10 mL |
| 2. | Biotin | 5 mg/50 mL |
Working stock solution:
Then prepare the final working solution by combining the following amounts of the two substock solutions plus thiamine HCl to 100 mL of purified water.
| Substance | Concentration (per 100 mL) |
|---|---|
| 1. Vitamin B12 (Cyanocobalamin) | 0.1 mL |
| 2. Biotin | 1.0 mL |
| 3. Thiamine HCl | 20 mg |
Dispense the working solution as 1 mL aliquots in cryovials for convenient use when preparing the medium. Store the remainder of the primary stocks and working solution in polyethylene bottles. Wrap vials/bottles with Parafilm to avoid moisture loss and store all solutions frozen.
References: Guillard and Ryther 1962, Guillard 1975
CHU-10 Variations
- CHU-10 Basic, i.e. the recipe above.
- CHU-10 with Soil Extract, (5-10% soil extract)
- CHU-10 with agar: add 15 g of Difco Bacto agar/L of medium)