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jeff courtman wrote:

>we've been using rheoscopic fluid from Kalliroscope.  our fluid seems to
>settle out, sometimes in as little as 12 hours. sometimes it will stay in
>solution for several days, unagitated. 
>
>we've been told precipitation could be do to water contamination
>(bacterial?).

Do you use the 'Bacterioscopic Stabilizer' that Kalliroscope supplies?

Do you use distilled water?

Is there any exposed metal in your system?  (We were warned that this 
would "dissolve" the particles in the rheoscopic fluid -- not sure 
why or how, but there it is.)


Our Kalliroscope fluid stays good for six months or more (granted, 
that's in a constantly agitated system)... not quite sure what we're 
doing that you aren't, but these are the first three ideas off the 
top of my head.  Good luck!

-- 
~~

Allan Ayres
Exhibit Developer
Lawrence Hall of Science
University of California, Berkeley
Berkeley, CA 94720-5200
[log in to unmask]
510-642-1254

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