Mustapha,

A lot of the decision depends on your application and micro vs. macro algae.  All preservatives changes algal cells somewhat.  If you simply want to measure describe morphology, 1-2% glutaraldehyde is usually recommended. 

See the SOP for the California water agency (http://www.waterboards.ca.gov/water_issues/programs/swamp/docs/sop_algae.pdf) and the description by Linda Graham at: http://www.botany.wisc.edu/courses/botany_330/preservation.html

For counting and ID, different preservatives (e.g. Lugol's iodine) are suggested.   Good luck!

John Wehr

why not try the storage solution for unicellular green algae (Bold 1967) consists of:

(for each stock solution, mass dissolved in a liter of distilled water)

1. NaNO3: 25 g

2. CaCl2 2H2O: 2.5 g

3. K2HPO4: 7.5 g

4. KH2PO4: 17.5 g

5. MgSO4, 7H2O: 7.5 g

6. NaCl: 2.5 g

7. EDTA

Dissolve 50 g of ethylene diamine tetra-acetic acid and 31 g of potassium hydroxide (KOH) in one liter of distilled water

8. Iron Solution

Dissolve 4.98 g of iron sulfate heptahydrate (FeSO4 7H2O) in one liter of acidified water prepared by adding 1 ml of sulfuric acid in 999 mL of distilled water.

9. Solution of boron

Dissolve 11.42 g of boric acid (H3BO3) in one liter of distilled water.

10. Microelements

Dissolving the following salts in one liter of water acidified:

ZnSO4, 7H2O 8.82 g

MnCl2 4 H2O 1.44 g

MoO3 0.71 g

CuSO4, 5H2O 1.57 g

Co (NO3) 2 6H2O 0.49

To prepare one liter of culture medium from the 10 stock solutions prepared in advance, mixing 10 ml of each of solutions 1 to 6, 1 mL of each solution 7 to 10 and up to one liter with water distilled,

For long term storage, it is preferable to change the solution every 3 to 6 months

Good luck 

Thanks

Mustapha,

A lot of the decision depends on your application and micro vs. macro algae.  All preservatives changes algal cells somewhat.  If you simply want to measure describe morphology, 1-2% glutaraldehyde is usually recommended. 

See the SOP for the California water agency (http://www.waterboards.ca.gov/water_issues/programs/swamp/docs/sop_algae.pdf) and the description by Linda Graham at: http://www.botany.wisc.edu/courses/botany_330/preservation.html

For counting and ID, different preservatives (e.g. Lugol's iodine) are suggested.   Good luck!

John Wehr

I've been using a modified Karnovsky's for years to fix Caulerpa (a marine green coenocyte)...

3% GTA, 2% FA buffered 16 ppt salt water 0.1 M  Nacacodylate buffer for 4 hours

rinse Nacac buffer 0.1 M 

post fix 2 hours in 1% OsO4 followed by same rinsing.

if you are interested in the rest let me know...since I'm not sure if you're just looking to "preserve" or if your intention is to do microscopy on them.  I'm happy to send you the whole protocol in word format. 

Cheers,

Ellen Lavoie 

Very interesting Ellen, thanks

You may find some useful guide from the website as below:

http://www.landcareresearch.co.nz/resources/identification/algae/identification-guide/identify

For freshwater specimens, I have made some combinations using Ethyl alcohol, formalin, acetic acid, and Chloroform. CuSO4 added in the ratio 10gm per 1000ml keeps the colour intact for years. Specimens remain good since 2004!