DIY items and Magnesium

> From: Doug Valverde <75051.160 at compuserve_com>
> Date: 17 Oct 95 19:43:11 EDT
> Subject: Dupla Cable Alternatives?
> Afternoon Everybody,
> I'm putting together a file on DIY items for planted tanks.  File currently is
> going into detail about how to assemble the various substrata heating systems.
> Eventually it will include DIY CO2, from manual to fully auto, DIY filtration,
> lighting options and so forth.  Covers from low tech to PC controlled high
> tech.

This ought to be fun.

> Anyway, I could use some help.  I have all the details about low wattage
> heating cables, including transformers, wire resistance and so on, so on low
> wattage I've got it pretty well covered.  But the high wattage, Dupla style,
> heating cables are give me fits.  Not in controls or transformer requirements,
> but wiring.
> Can anyone give me details about Dupla's wire, and if possible alternatives to
> Dupla's cabling?  Would appreciate ordering information as well.

I have a few leads on cable alternates I've archived on the Krib in the
"Plant Tech" directory

One is a silicone-sealed medical cable (posted on APD many months back).  
It's quite expensive though, so in the long run you may not save much 
over Dupla.  Another alternative (gleaned from rec.aquaria around the 
same time) is PVC-insulated Nichrome wire, made by Belden.  I actually 
have some of this and am going to try it out when setting up my next tank.

The Shameless plug: The Krib actually has every original DIY article I've 
ever seen on the net.  If I haven't seen it, I want it there. :)
You'll find a number of articles on constructing cable heating, CO2, 
lighting (though not as fully covered because not as common), 
fertilizers, etc.  You might find a lot of resources there.  Also check 
the FAQ for condensed versions (the Krib is like a collection of cut-out 
magazine articles, the FAQ is like a book written by people from reading 
all the magazine articles). :)

> From: olga at arts_ubc.ca
> Date: Tue, 17 Oct 1995 17:04:59 -0700

> And, last but not least: HOW does one disolve magnesium in aquarium
> water??? I have some magnesium tablets but trying to mix them with water is
> hopeless. Is there something liquid I can use to get some magnesium into
> the tank?

I found magnesium carbonate dissolves about as easy as calcium
carbonate...  that is to say, slowly but eventually.  Maybe you could use
a mortar and pestel to powderize the tablet.  Or put the tablet into the
filter flow (mix in prefilter chamber, for instance) so that lots of water
rushes by it. 

       - Erik
Erik D. Olson					         amazingly, at home
eriko at wrq_com