Cecil, I picked up some info on Bentonite at a recent Seminar from a place called Texas Sodium Bentonite, Inc. They list contact info as follows.
George Burton-Sales Supervisor
Rt.3 Comanche, Texas 76442
(915) 885-2339 day/night
(915) 885-2138 Fax
(254) 842-7912 mobile
E-Mail: bentonite@itexas.net
Web site:
http://www2.itexas.net/~bentonite Their literature does invite questions.
Under "How can I learn more about Sodium Bentonite" it says:
"Please include the following information with your correspondence: size of pond, soil type(if possible), location of pond(city, state, zip code), your phone number, fax number or mailing address, so that additional information may be sent."
I have never talked to them but figure if I ever decide to try bentonite again, I will ask for instructions next time. So far, I've gotten my advise from the oil well crowd and it hasn't worked.