... or with related improvisations.

Found we had this hole in the archives, so I'll begin filling it.

Secchi disk configuration, origins, and usage (Cary martin's post is the best part): http://forums.pondboss.com/ubbthreads.php?ubb=showflat&Number=67980&page=1

Last edited by ewest; 03/15/11 10:49 AM.

"Live like you'll die tomorrow, but manage your grass like you'll live forever."
-S. M. Stirling
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