Re: How would household bleach effect the growth of phytoplankton? How would it

Kelly,

Bleach (sodium hypochlorite) is toxic. We tend to take it for granted 
because it is a household chemical. However, bleach is a strong oxidizer 
that can cause severe damage to living material.  In fact, the toxicity of 
bleach is such that it is often used as a disinfectant, and microorganisms 
have not developed resistance.

Algae and plants are no exception to the toxicity of bleach. This is why 
millions of people add sodium hypochlorite to their swimming pools and 
municipalities chlorinate the water supply.  It is not the presence of 
chloride ions that makes bleach toxic, but the added oxygen in bleach.  
This is highly reactive and oxidizes most organic compounds.  Oxidation 
of colored chemical compounds results in bleaching.  Please see 
http://howstuffworks.com/
question189.htm for more detailed information.

Remember plants and algae rely on a variety of colored compounds for their 
livelihood.  These include chlorophyll, of course, but also carotenoids and 
other "antenna" pigments and protective pigments.  When these are damaged 
or bleached-out, plants cannot photosynthesize.  

Sodium hypochlorite also produces hydrochloric acid when in solution.  This 
acid has toxic effects all its own.  For example chlorophyll is very 
sensitive to exposure to acid conditions.  

Dunaliella has been the subject of many, many studies in phycology and 
plant physiology.  This is largely because it is the algal version of a lab 
rat.  It is easy to grow, and seems to thrive under laboratory conditions 
which make it the ideal candidate for physiological research.

I will not go into details of culture here.  These are treated well in many 
publications.  For easy access to information on algal culture I will refer 
you to the Phycological Society pages and links located there.
http://www.psaalgae.org/l
inks/links.html
Another very valuable resource is the Provasoli-Guillard Center for the 
Culture of Marine Phytoplankton.  Their site has a wealth of information on 
algal culture including culture conditions and media recipes and is 
available at: 
http://ccmp.bigelow.org/  

Hopefully helpful.