Here's Seachem's reply to my question. It seems to support both views, which is good, since both
are "right".
"Dear *****,
As Diana Walstad said, in the vast majority of tanks Equilibrium is fine to use. Theoretically a tank with a large amount of anaerobic areas could have problems with hydrogen sulfide production. In her book she also mentions that oxygen released by the roots and soluble iron give the plants some protection. We have not experienced this problem nor have we had any reports from customers on this problem.
Best Regards,
Seachem Tech Support~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Seachem Laboratories, Inc.
http://www.seachem.com 888-SEACHEM
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