I am trying an experiment on ferrofluids.  I bought "The Ferrofluidic
Adventure Science Kit " from www.teachersource.com. It comes with 50cc
of ferrofluid and also a "display cell". The display cell is a plastic
testube with ferrfluid in a clear solution. From reading the
datasheets with the product and some online searches I figured that
the test tube has a 50:50 solution of isopropyl alchol and deionised
water. which prevent the ferrfluid in it from wetting or staining the
glass. NOW the problem is ... I took a testube, put in a 50:50
solution of isopropyl alchol and deionised water. And it is still
staining the GLASS!!!! What I observed however was, if I took this
solution and applied a stong magnetic force to it, and then let the
stained ferro stay in the container. removed the rest into another
container, let is stain that, move it to another container (with the
solution) the ferrofluid becomes more stable. But over night i left it
in a glass container, morning it has stained the glass again) The
testube I got with the KIT does not stain is not matter how much you
shake it, apply magnetic forces whatever. WHY???? I need to make an
invitation on the theme of "all it takes is magnetism" with the
ferrofluid forming a lotus shape when placed on a magnetic base. Its
for my precious aunts 25th wedding anniversary. So how do I get it to
never ever stain the glass container???? NEED HELP REAL BAD.



 the link to that item is
http://www.teachersource.com/catalog/page/Electricity_Magnetism_Engines/Ferrofluids/?id=48968364a05e2c7052e76cab6fe374d3

In the link it says the container is plastic. Are you using glass
tubes? Ferrofluid is wonderful stuff isn't it?!

I've never done anything with it that didn't involve it staining
anything it touched.

It also seems possible that the ferrofluid in the tube you are trying
to copy has a different carrier or surfactant.

Sorry, the final product is going to be in a form of plastic, the ones
they have for making unbreakeable lens (spectacles). But i am testing
staining on glass for now. Yes the ferrfluid display cell is made of
plastic, but it has two display cells, one plastic and one in glass.
Also I noticed one more queer thing, the clear solution turns a little
yellowish/ My feeling is that the Isopropyl alcohol is dissolving some
of the  oil, and that's why some particles stain the glass. Not
sure.... Yes ferrofluids are awesome, if i can figure a way to handle
this well I have a lot of ideas where I think I'd like to use them.
Thanks for taking the time to comment egon.