Use ethanol.

Gianluca Stasolla sir Macroalgae and the attached microalgae can be collected by hand or with a knife, including part or all of the substrate (rock, plant, wood etc.) if possible. you can Search all habitats in the waterbody including the edge of stones in fast-flowing water, aquatic plants, dam walls, and any floating debris.

In running or slightly turbid waters, a simple viewing box made from transparent perspex enables attached algae to be more easily observed. A hand lens is often useful to determine if material is reproductive (essential for species determination in some genera and helpful for generic placement).

Microscopic floating algae (the phytoplankton) can be collected with a mesh net or, if in sufficient quantity (i.e. colouring the water), by simply scooping a jar through the water. Water samples can be left overnight allowing the algae to settle and concentrate on the bottom of the container. Squeezing Sphagnum and other mosses, or some aquatic flowering plants such as Utricularia is a good way to collect a large number of species.

Microscope slides suspended in a waterbody for c. 2-4 weeks will reveal many species. The slides should be kept submerged until ready to examine under the microscope. One side can be wiped clean and a coverslip placed over the other.

Algae growing on soil are difficult to collect and study, many requiring culturing before sufficient and suitable material is available for identification.

@Si Mokrane Siad

@Bejawada Chanikya Naidu

wow

informative qustion

Me too I work on the different classes of freshwater phytoplankton and the answers to this question interest me a lot.

We can preserve algal sample in 4% formalin for longer period.

Hello:

I would suggest to keep the living diatoms in plastic bags, not tubes, on ice in cooler.

Diatoms are organisms that are very resistant to environmental conditions. In order for them to stay alive for up to a week, it will be enough to take a light-permeable plastic bag with enough water and air together with the environment you have sampled (as is the case with aquarium fish). However, do not expose it to direct sunlight to avoid getting too hot.

After sampling, add few drops of sample (subsample) with most commonly used culture media for diatoms viz; WC, COMBO or BBM (details- Algal culturing techniques by Robert Anderson). The ratio of Sample: Medium- 1:1.

Culture medium + low temperature storage + aeration (as mentioned above by Oliver Skibbe) support the growth and viability of diatoms, and eventually benefits for live diatom observation.

Dear Gianluca Stasolla,

Keep the diatoms in transparent plastic or glass containers on the same substrates that you collected such as clay, plants and rocks, then add water to them from the same place of collection, and they must be provided with appropriate lighting, also you can add culture media such as F3

best wishes in your work

I would suggest conserving them in a transparent plastic container and under lower temperatures.

Preserve the diatom sample in Lugol's solution (5% iodine and 10% potassium iodide w/v).

Dear Gianluca Stasolla

Diatoms are very demanding on abiotic factors (temperature, water salinity, etc.). Therefore, it is necessary to recreate their living conditions.

Gianluca Stasolla the links am sharing shows about the methods for collection and preservation of diatom samples and its a pdf and am sure its a perfect document

https://docs.niwa.co.nz/library/public/1770054839.pdf

another fresh water algae collection n storage _ basic one

https://plantnet.rbgsyd.nsw.gov.au/PlantNet/fwalgae/Introduction/collect.htm

Many thaks!

Sampling and preserving live freshwater diatoms for observation involves careful collection, handling, and storage to maintain their viability and integrity. Here's a step-by-step guide on how to do it:

Sampling:

Preservation:

Observation:

Remember, live diatoms are highly sensitive to environmental conditions and can die quickly if not adequately preserved. Immediate preservation after sampling is essential to maintain the diatoms' viability for observation. Additionally, make sure to handle the samples with care and avoid exposing them to extreme temperatures or contaminants that could compromise their integrity.

Note that the above method is suitable for observation purposes. For scientific research or more detailed studies, additional preservation techniques or fixation methods may be required, depending on the specific objectives of the study.