DIY Alkali Media Recipe (for spirulina)
Our Spirulina Nutrient Solution Preparation
Below are instructions on how to make the spirulina media, or you can simply buy it from our store! Here is our link.
First prepare the necessary stock solutions. Next, prepare Solutions I and II; Solution II includes 1 mL of the trace metals stock solution but not the vitamin stock. Autoclave Solutions I and II separately and cool; aseptically combine the two solutions. Aseptically add 1 mL of the cyanocobalamin (B12) solution.
Table 1: Chemical Composition
| Components | Stock Solution | Quantity | Molar Concentration in Final Medium |
| Solution I | 500 mL | ---- | --- |
| NaHCO3 | --- | 13.61 g | 1.62 x 10-4 M |
| Na2CO3 | ---- | 4.03 g | 3.80 x 10-5 M |
| K2HPO4 | --- | 0.50 g | 2.87 x 10-6 M |
| Solution II | 500 mL | --- | -- |
| NaNO3 | -- | 2.50 g | 2.94 x10-5 M |
| K2SO4 | --- | 1.0 g | 5.74 x 10-6 M |
| NaCl | --- | 1.0 g | 1.71 x10-5 M |
| MgSO4 7(H2O) | --- | 0.20 g | 8.11 x10-7 M |
| CaCl2 2(H2O) | -- | 0.04 g | 2.72 x 10-7 M |
| FeSO4 | --- | 0.01 g | 3.60 x 10-8 M |
| Na2EDTA | --- | 0.08 g | 2.15 x10-7 M |
| Trace Metals Solution | (See table 2) | 1.0 mL | ---- |
| Vitamin Stock Solution | (See table 3) | 1 mL | --- |
Trace Metals Solutions
Begin with 900 mL of dH2O and dissolve the EDTA. Independently, dissolve each component and bring final volume to 1 liter. Schlösser (1994) recommends making two trace metals solutions, (a) 0.4 g EDTA and 0.7 g FeSO4 7H2O in 100 mL dH2O, and (b) 0.4 g EDTA and remaining elements in 900 mL dH2O; autoclave separately and combine aseptically when cool.
| Components | Primary Stock Solution | Quantity | Molar Concentration in Final Medium |
| Na2(EDTA)2(H2O) | --- | 0.8 g | 2.15 x 10-6 M |
| FeSO4 7(H2O) | --- | 0.7 g | 2.52 x10-6 M |
| ZnSO4 7(H2O) | 1.0 g L-1 dH2O | 1 mL | 3.48 x 10-9 M |
| MnSO4 7(H2O) | 2.0 g L-1 dH2O | 1 mL | 8.97 x10-9 M |
| H3BO3 | 10.0 g L-1 dH2O | 1 mL |
1.62 x10-7 M |
| Co(NO3)2 6(H2O) | 1.0 g L-1 dH2O | 1 mL |
3.44 x10-9 M |
| Na2MoO4 2(H2O) | 1.0 g L-1 dH2O | 1 mL |
4.13 x10-9 M |
| CuSO4 5(H2O) | 0.005 g L-1 dH2O | 1 mL |
2.00 x10-11 M |
Cyanocobalimin Stock Solution
Dissolve the cyanocobalamin in 1 liter of dH2O and filter sterilize. Store frozen.
Table 3: Vitamin Composition
| Components | Primary Stock Solution | Quantity | Molar Concentration in Final Medium |
| Cyanocobalomin | --- | 0.5 mg | 3.69 x 10-9 M |