Bill,
I did not probe Jerry when he said that they used NSW. The actual context of the conversation was him asking me if I used NSW as they did. When I showed him my system volumn he acknowledged that it would be too expensive for my commercial operation.
I will send him an email, to ask him if I am out of text with their procedure.
Patrick
We get filtered seawater from the Marine Science Institute in Port Aransas, Texas. The water is pumped from about 100 meters off shore into a large settling tank, is generally left undisturbed for multiple days to settle particulates, and then is filtered through a standard string filter before we get it. We collect the filtered seawater in 20-liter hard polyethylene carboys and can store it at room temperature in complete darkness for at least 6 months without any evident microbial growth or salt precipitation.
Near-shore seawater can vary significantly in salinity. Thus, when we are ready to use some of the stored seawater, we check its salinity and (if necessary) add a small amount of distilled water or Instant Ocean to bring the salinity to 30 PPT - within 1 PPM. After adding desired additional nutrients (typically nitrate and/or phosphate), and thorough mixing, we pasteurize it on two successive days, with cooling to room temperature for at least 18 hours between the two heat treatments. This "tyndallization" process is done in glass containers that don't have any internal scratches, in order to avoid seeding crystals that would lead to salt precipitation. If vitamins are required for a particular medium, they are added to the cooled seawater after the final pasteurization. The pasteurized seawater, with or without enrichment, is then kept covered and stored at refrigerator temperature in very dim light or darkness. We prefer to use it for inoculating algae within 2 months after it has been prepared.
Some of our red and green macroalgae can be maintained without disturbance (no mixing or carbon dioxide enrichment) in this media for 6 months or more, where they grow rather slowly without significant contamination under 12h:12h day:night cycle AT relatively low light intensity.
In growing many different strains of marine microalgae and macroalgae, we have not observed any significant differences in the use of natural sea water and Instant Ocean. Transport of natural seawater is somewhat expensive, which we moderate by hauling 150 gallons at a time. I am not certain of the cost difference, when labor is included, between using Instant Ocean and natural seawater.
There are surely significant differences in our requirements and the needs of those who manage large marine aquaria. I would be interested in seeing the comments of those who criticized the use of natural sea water.
Jerry
PS: second email
Hello Patrick,
I don’t want to get into correspondence with this group because of my time constraints. You may post what I wrote, but please first change that “AT” to small letters.
I saw your post and should correct a few points.
I am not the head of a college but am a professor in the Department of Molecular Biosciences at the University of Texas. My other title is Director of the Culture Collection of Algae (known as UTEX) at the University of Texas at Austin. Our collection of microalgae might possibly be the largest and most diverse in the world, but several others are quite comparable in size. Our collection of algae was first established in 1952 as the only major publicly accessible repository of algae in the Americas. The focus was primarily on freshwater and edaphic algae, although some marine microalgae and macroalgae were maintained. The NCMA in Bigelow Maine was established some years later as a marine phytoplankton collection. Since then UTEX and NCMA have remained the primary general repositories of algae in the USA, with UTEX focusing more on freshwater species while NCMA includes mostly marine species. However, both collections work with freshwater and marine scientists, and both include marine and freshwater strains.
Jerry
PS: Jerry is more humble than I. I was incorrect on some detail, which he has corrected in his two emails.
