Re: Aquatic Plants Digest V5 #468

[Bill Wichers <billw at waveform_net>]

>My space is 4 inches.  The porch is cinderblock and
>the screen windows are framed out with 2X4.  This
>leaves a nice self for small potted plants.  I have a
>layer of .8mil covered with 4mil on both interior and
>exterior.  Some of this is multiple layers as I'm not
>as good at measuring as I thought when cutting.

Probably no need for a blower then if your space is that large.

>After I set this up my landlord informed me that this
>exterior porch has a sheetrock ceiling.
>
>?????

Sheetrock is essentially concrete on a mesh layer with the whole assembly 
being formed into a thin sheet. You can think of it as a super-duper grade 
of drywall :-) It should be immune to moisture. It will NOT be a good 
thermal insulator though, you might want to stick some foam-board 
insulation to it.
but this it typical of this house.

 >It has an actual
>fuse box.  And it is all 2 wire.  All my things are 3
>prong.  I buy a lot of adapters.  I can't even instal
>a GFI because there is no groundwire so there wouldn't

You might have a ground wire in the box even if there isn't a three-prong 
plug. My house here is wired like that, and I just went around and swapped 
out all the plugs and hooked up the ground wire that was in the boxes 
already. The electric code also allows you to run a separate ground wire 
from a non-grounded box back to a cold water pipe (although the best place 
is the house's central ground, which you WILL have at the panel even if you 
don't have grounds in the fixtures)

You can install a GFCI in a non-grounded box and it will still work, but 
you can't expect the pseudo-ground you get to work for things like ground 
probes or surge protectors. You'd be best off running a separate ground 
wire as I mentioned above.

>be a point.  And in at least one outlet, the polarity
>is reversed.  I know because I had my desk top pluged
>into one, my laptop plugged into another, and
>connected the phoneline between them.  I was lucky. It
>only instanly burned out my PCMCIA card controler on
>the laptop.  So now there is no way to hook a modem to
>the laptop, so it is now a glorified gameboy. (yes I
>have an emu).

You have something else going on that you should look into. All phone-line 
connected devices that get power that isn't derived from the phone line are 
required by the FCC to be electrically isolated (with a transformer) from 
the phone line to avoid exactly this kind of problem. Reversed wiring in a 
plug won't cause failures with electronic equipment since AC "polarity" 
(not really polarity for AC, it really has to do with phase) isn't really 
important to the power supplies in electronic devices. Whatever is causing 
your problem may be dangerous and you should have it checked out. Check 
with an electrician for the power and your phone company for the phone 
line. If your phone line and electrical power wiring is connected together 
anywhere you have a *serious* and very *dangerous* electrical problem!

>i just hope the addition added in the '70s wasn't
>wired with aluminum....

Easy to check. Is the wire silver colored? If it is it is aluminum for 
sure. You can also get copper-clad aluminum but most fixtures will be OK 
with that. If you have aluminum wiring make sure to use antioxidant paste 
on any connections you make.

         -Bill
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Waveform Technology
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