I culture my own Phytoplankton, thus I KNOW its live. Culturing it is simplicity itself; a vessel, sterile saltwater, a sun-like light, Guillard's F/2 formulae and a starter culture.
Some time ago I wrote a six-part series on culturing various freshwater and marine organisms. I reproduce the section on Phytoplankton below.
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PHYTOPLANKTON
Equipment
A clean container; glass is better.
Sterile freshwater or marine water
An air pump and airline.
A starter culture
Guillard's F/2 algae nutrient
A turkey baster or eye dropper, depending on the size of your culture
A bright light.
I use five-gallon glass carboys, but you can use any clear container, the size based on your need. Sterilize the culture water by boiling it in a clean pot, then pour it into the container. Mix the water with Guillard's F/2 formulae, the amount based on how much water is used. Use the air pump to put out large moderately slow bubbles out the end of the air line. Place the airline as low as you can get it in the culture vessel.
You'll need a starter culture from a biological supply house. I use lfscultures.com and aquaticeco.com as my sources for starter cultures.
The freshwater algae to look for are Selenastrum, Ankistrodesmus, Scenedesmus, Chlorella and Euglena.
The marine algae to be concerned with are Nanochloropsis, Isochrysis and Tetraselmis.
You can culture two species or more, with a variety better than a single kind.
The starter cultures can come in liquid form or (better) on a petri dish. For the latter, fill the dish with sterile, fertilized water and place it under a moderate light; a window with indirect sunlight is perfect. In about a day the dish should be deep green (or yellow-green, depending on the species). Take a clean cotton swab, rub some off, and dip and shake the end of the swab into your fertilized culture container. Do it until about the dish is empty.
Each species should have its own vessel. Mixing species is ill advised, as some species are better at processing nutrients than others, meaning you'll just have one species in the culture.
Turn on the bright light. I use metal halide pendants, but a T5 or VHO fixture suspended about six or eight inches above the culture will do. Bulbs should be 6700K to 10,000K for optimal growth.
You will see the water turning progressively more and more green. In a week to 10 days, it'll be deep, deep green and ready to harvest some.
I use a turkey baster. Any you remove replace with more sterile water. As long as the culture is kept bright and the removed water is replaced with fertilized culture water, the culture can be kept going indefinitely.
In a future installment you'll learn all you can do with that green water.
Dave
