Dry Weight vs Cell Count

Dry weight is the weight of the product the water removed.  At Reed Mariculture, we measure dry weight in our microalgae products by placing 100 grams of algal concentrate into an 80°C drying oven and heating until a stable weight is reached.  The weight of the residue is then used to calculate the dry weight.  For Nanno 3600, 100 grams of concentrate will yield 18 grams of dry residue, hence it is an 18% dry weight product.

The reason we specify the concentration of our Instant Algae products by dry weight, and not by cell number, is because there is such a large difference in cell volume (and biomass) for a small difference in cell size. For example, Isochrysis is around 5 µm in diameter...

Diameter 5.0 µm, cell volume = 65.4 µm3
Diameter 5.5 µm, cell volume = 87.1 µm3

So an increase of just 10% in the diameter means a 33% increase in volume (and biomass)!

A 0.5 µm difference in dimension is difficult to measure by microscopy, especially in cells that are not perfect spheres. Algal cells in culture are growing and dividing, so there is a range of sizes from newly divided to just ready to divide. The 2 daughter cells from a new division have the same biomass as the mother cell, even though there are now twice as many cells. So cell number is of very limited value in specifying the feed value of algae, even for a single-species product. For Shellfish Diet, even just considering the roughly spherical cells (Thalassiosira weissflogii cells are cylindrical and can vary greatly in length):

Isochrysis at 5 µm diameter, cell volume = 65.4 µm3
Tetraselmis at 12 µm diameter, cell  volume = 905 µm3

For comparison, Nannochloropsis cell sizes vary from 1-2 µm depending on growth conditions and where the cell is in its “cell cycle,” i.e. having just divided, growing, or ready to divide into two cells.

1  µm diameter, cell volume =  0.524 µm3
2  µm diameter, cell volume =  4.19 µm3

For this reason, cell number is not very informative of food value. A given biomass of filter feeders requires a certain biomass of phytoplankton to support metabolism and growth, not a certain number of algal cells. The only way you can reliably calculate your required feed rates is to consider the biomass of your animals and the biomass/dry weight of the algal feed.

Live vs. Non Viable Algae

Instant Algae® products are non-viable algae, meaning that they cannot be used to start cultures. However, very few aquaculture applications require microalgae that reproduce, and there are several advantages to using a non-viable product:

Stable nutritional profile - live algae need nutrients (plant fertilizers) and adequate light to remain healthy, but these are not normally provided during the feed-out process so the nutritional quality can rapidly decline. Instant Algae© do not need nutrients or light so they maintain the same nutritional profile in your refrigerator or in your tank.

Super High Rotifer Concentrations - With live algae it is difficult to obtain rotifer densities higher than 1-2,000/ml. With Instant Algae® it is easy to achieve concentrations in excess of 5,000/ml.

Easy to Capture, Faster Feeding

Excellent Suspension, No Clumping, No Fouling - Unlike powered feeds, Instant Algae® will stay suspended in the water column for 1-2 days with minimal water circulation required. Unlike dried algal cells that rapidly leach soluble components that can stimulate growth of bacteria,  Instant Algae® cells are intact.

Typical Nutritional Analysis of our Microalgae 

 

Proximate Analysis (% of dry weight from algae)

  Nanno Tetraselmis Pavlova Isochrysis TW
Thalassiosira
weissflogii
TP
Thalassiosira
pseudonana
Dry Weight 18.2 % 18.2% 8.2% 8.2% 8.0% 8.2%
Calories (100g dry wt algae) 450 390 400 450 390 316
Protein 62% 63% 43% 44% 43% 45%
Lipid (Total) 18% 11% 20% 19% 5%  10%
Carbohydrate 9% 11% 26% 25% 12%  12%
Ash 10% 15% 10% 11% 40% 33%
Vitamin C 0.85 % 0.25 %   0.4 %    
Chlorophyl A 0.89 % 1.42 %   0.98 %    

 

Amino Acids (% of total)

  Nanno Tetraselmis Pavlova Isochrysis TW
Thalassiosira
weissflogii
TP
Thalassiosira
pseudonana
Aspartic Acid 9.40 8.95 7.27 10.36 12.18 4.13
Serine 4.31 3.71 3.33 3.86 7.42 1.86
Glutamic 15.48 17.59 15.47 11.42 17.13 4.67
Glycine 7.11 5.93 4.75 6.78 7.83 2.27
Histidine 0.61 0.19 0.50 0.23 0.43 0.80
Arginine 4.57 4.59 4.11 4.39 2.82 2.21
Threonine 5.28 4.40 3.51 4.88 5.38 1.81
Alanine 1.54 7.62 5.66 7.55 8.57 2.51
Proline 15.20 6.47 7.34 12.48 8.65 1.47
Tyrosine 1.06 1.84 1.29 2.84 0.60 1.53
Valine 6.90 5.00 4.56 5.49 5.02 2.04
Methionine 2.64 2.55 2.10 3.79 2.01 1.01
Lysine 9.07 8.20 4.65 6.96 7.59 2.42
Isolucine 1.47 0.97 0.16 1.11 1.78 1.87
Leucine 11.57 7.94 7.19 6.87 9.21 3.23
Phenylalanine 1.92 3.51 26.72 8.52 1.25 2.21
Taurine 0 10.55 0 0 0 0.13

 

Fatty Acids (% of total)

  Nanno Tetraselmis Pavlova Isochrysis TW
Thalassiosira
weissflogii
TP
Thalassiosira
pseudonana
12:0 0.3 0.2 0.0 0.0 0.0  
14:0 2.9 0.4 15.5 12.5 6.4 9.648
15:0 0.2 0.1 0.2 0.5 2.5  
15:1 ND

 

ND ND

 

 
16:0 18.6 14.4 7.9 9.2 13.5 17.152
C16:1           35.835
16:1n7 20.0 0.8 9.5 6.3 13.9  
16:2n4 0.3 ND 0.7 0.5 2.6  
17:0 0.3 2.0 0.2 0.2 0.4  
16:3n4 0.6 1.2 0.5 0.6 11.6  
18:0 0.4 0.3 0.3 0.3 0.4  
18:1n9 3.2 5.1 0.7 10.1 0.6 6.279
18:1n7 1.0 2.2 0.3 1.6 0.5  
18:2n6 3.5 5.0 1.2 5.7 1.6  
18:3n6 0.6 ND 0.2 1.3 0.3  
18:3n4 0.1 0.0 0.1 ND 0.3  
18:3n3 1.2 15.0 0.9 5.5 0.7  
18:4n3 0.1 7.7 10.0 17.8 1.1  
20:1n9 0.0 1.1 ND 1.7 0.2  
20:2n6 0.0 0.1 0.1 0.1 0.0  
20:3n6 0.3 0.1 ND 0.1 0.1  
20:4n6 2.7 1.1 0.9 0.4 0.9  
20:3n3 0.3 0.5 0.1 0.9 ND  
20:4n3 0.2 0.4 0.5 0.1 0.5  
20:5n3 28.7 5.4 22.0 1.8 19.6 20.521
22:5n6 0.0 0.1 7.6 1.7 0.2  
22:5n3 0.1 0.1 0.1 0.2 ND  
22:6n3 0.3 ND 6.2 11.2 4.2 6.279

NOTE: Instant Algae is grown using a modified F/2 formulation. These analysis are not guaranteed. The profiles on the algae change during the year due to varying amount of sunlight, temperature, and photo period.

Biosecurity

All Instant Algae® products are free from pathogenic viruses and bacteria. Vectors for contamination are excluded by our biosecurity protocols and our site's inland location,. Instant Algae® are not axenic (bacteria-free),. however the bacteria present are probiotic or benign and none are pathogenic to marine organisms.

Safe Water Source,  Fully Contained, Recirculating Artificial Seawater System

The water at our facility is NOT ocean water. Our on-site well supplies fresh water from a depth of 200' feet. The water is pasteurized at 160 °F  (71 °C) for 10 minutes, then salts and nutrients are added to create artificial seawater. . The water is 100% recirculated and continuously passes through a clean-up and pasteurization process using a protein skimmer, ozone treatment and pasteurization. A custom-designed computer monitoring system maintains all of these systems to ensure reliable pasteurization of the water.

Secure Location

Our algae-growing facility is located in the foothills near San Jose, CA. It is many miles from any type of fish, shrimp, or shellfish operation and so there are no opportunities for marine pathogens to be introduced. The site is used exclusively for growing algae and zooplankton that have passed our quarrantine and pathogen testing  protocols. No pesticides are used at our production site.

Growing Process

Instant Algae is grown using closed photobioreactors, to prevent contaminants from entering the systems.

Microalgae Starter Cultures

Reed Mariculture's Instant Algae® microalgae products are non-viable and will NOT work as starter cultures. The following are links to universities and other organizations that do provide microalgae starter cultures:

North America

Europe

Australia

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