Generally the order of metal toxicity which affects the algal species is Hg> Cu>Cd>Ag>Pb>Zn. Mercury being the most toxic metal affects the enzyme systems of the algae and inhibits their functions. Copper is used to control the algal blooms in fresh water. The extent of toxicity depends on the ionic content or free Cu2+ ions available in the algal culture and not the total copper concentration.

yeah right. i got confused. i would stick with a culture system without any carbon source than CO2.

The algae meal or cake can be used for just about anything. I'm sure most algae will have a high BTU compared to most kinds of biomass and even lignite coal even after oil extraction, but before you go throwing that stuff into a gasifier you might want to ask yourself if there is other sources of fuel around aside from algae that is less valuable and more available. Since anything from plastic to human solid waste can be gasified, it seems more prudent to use that highly nutritious algae meal for food, pharmaceuticals, vitamins,cosmetics, textiles, fabrics, paper fiber, building materials, bioplastics, alcohols and/or chemicals and just use the algae meal as a back up when needed for the gasifier. I think gasifiers should be used in tandem with algae systems but only to utilize the solid waste that algae cannot consume while feeding soluble waste to the algae including the co2 from the gasifier and toilet water from the house. Burning algae is way better than burning anything else for economic and environmental reasons, but with so many organisms to feed and so much available unneeded waste to burn, its just not economical to do so right now. However, I believe algae is the future and that it will be grown anywhere that there is pollution. So while regular gasification companies benefit from free garbage to burn for some time they will still eventually have to invest in growing algae to burn once all of the garbage is gone.

It all depends on how dense your sample is, how accurate you want to be, and what magnification you're using. Most SR cells don't have grid lines, so you must have that in your ocular lens. The best (most accurate) method would be to use an stage micrometer slide (eg http://www.tedpella.com/histo_html/2280-10.htm) and measure the length (and height) of your grid at a set magnification, and then determine how many of those squares "fill" your SR cell, which should be 50mm long x 20mm wide and 1mm deep = 1 ml (http://www.2spi.com/catalog/standards/sedgewick-rafter-counting-cell.shtml) Here's what I share w/ my students: Sample Collection Procedure Attach the 64um plankton net to a pole and holding the net away from the body, to the side, drag the net barely beneath the water’s surface for 100 meters. Take care not to drag the net on the bottom of the lake. Slosh the net up and down in the pond without submersing the mouth of the net in the water, to dislodge all the organisms that may be clinging to the inside of the net. Allow the excess water to drain out of the net. Carefully empty the contents of the collecting bottle into a labeled container. Add preservative to the container upon return to the laboratory.. Analysis Procedure In order to estimate the amount of plankton organisms in a lake, we count the amount in a sample of known volume, and then multiply by the volume of the lake. Stir the bottle of preserved plankton so that the plankton are momentarily uniformly suspended in the lake water. Using a syringe-pipette device, draw out 1 mL and discharge the water into a Sedgewick-Rafter Counting Chamber. Cover with a 22x50 mm cover slip. Before beginning the plankton counts as described below, scan your slide and familiarize yourself with the various types of plankton using the photographs and identification guides. Each class member will take one phytoplankton and one zooplankton count and then give their results to the phytoplankton and zooplankton teams. Phytoplanton count: With the microscope on the 100x magnification, focus on 3 random fields of view. For each view, use the illustrated tally sheet to identify and count the number of phytoplankton in the selected field. For filamentous algae like Spirogyra and Ulothrix, count each cell in the filament as individual cells. For colonies like Dinobryon and Anabaena, count each colony as one individual. Give these 3 counts to the phytoplankton group. Zooplankton count: With the microscope on the 32 or 40x magnification, focus on 3 random fields of view. For each view, use the illustrated tally sheet to identify and count the number of zooplankton in the selected field. Give these 3 counts to the zooplankton group. Calculation of # plankton/ml: Each plankton team will then total the counts for each type of plankton recorded and determine an average number of each type in a field of view. To get numbers per ml, multiply the average value by 431 for phytoplankton (at 100x), by 28 for zooplankton (32x), or by 86 for zooplankton (40x). Hope this helps. Good success, John PS Another useful ref. just now saw: http://www.vic.waterwatch.org.au/file/inform/Biological%20Surveys_Algae.pdf

The DEO has a patent like this for sale right now. I read about it a few months ago but we are some ways off from comercialization.

Thanks for reply . Actually, I will try to cultivate Dunaliella on wastewater and evaluate the productivity .Do you have any idea around that? I Think it is more acceptable to use the biomass for biofuel than betacarotene or gycerol.Do you think so?