Re: JoAnn's plant nutrient experiments

[JoAnn Amber <elmtreeacademy at yahoo_com>]

Wow, Steff!  Thanks!

Sodium nitrate it is, then.  Sounds straightforward
enough; I didn’t want to get into that
add-this-compensate-with-that if I didn’t have to.
Gets pricey. *grin*

Good point about the ion concentration.  Admittedly
it’s fine-tuning, but it’s also good math practice as
well as a springboard for chemistry discussions. To
say nothing of it being better lab practice. ;)

<snip>
Finally, nitrate salts are all pretty reactive. Be
moderately careful.
<snip>

Not to worry. I’m pretty fussy about lab safety. :)

Good idea about making stock solutions.  Measuring all
those individual portions would indeed be a major
pain.

<snip>
Us geeks call this kind of single dose an "aliquot,"
which we also use as a verb
<snip>

Aliquot, eh?  I remember *hearing* the word a few
times, lol!  How on earth do you use it as a verb? 
I’ll have to work on using ‘aliquot’ since I’m a geek,
too, and I wouldn’t want to make a geek faux-mot. ;)
I’m an engineering geek, though, not a science geek,
so maybe I’d be forgiven.

<snip>
Would you measure growth by length, number of leaves,
weight-when-blotted-dry ?
<snip>

*grin*  That is one of the questions I intend to ask
the kids.  I’m betting they won’t have thought about
just what they mean by growth. ;) I thought I’d let
them decide, maybe even have them measure multiple
parameters and see if one measurement is a ‘better’
indicator of growth/health (in their estimation) than
another.  Lots of interesting questions there: would
length be a good measure of growth in a multi-branched
plant?  How do you account for dropped leaves?  Yadda,
yadda, yadda.

Thanks for the guidance on slowing the algae
infection.  I hadn’t given enough thought to that one.
 Starting ‘clean’ should give us enough time to get
through the experiments before the algae take over.  I
don’t have to grow them forever, lol!

Replicates!  Duh! [slapping forehead]  I can only hope
that would have occurred to me before we started. 
Sheesh!  See why I need some input on this?

Thanks so much for your help, Steff!  I appreciate you
taking the time to read and think about the
experiment.
JoAnn


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