Multiple Copies/Sand/What Plant/Coils

> From: tchtoo at eskimo_com (Ted Hossfeld)

> Dear Hardjono,
> I got two copies (seperate transmissions) of today's Digest.  See below.
> This happens every so often.  Please look into what can be done to see that
> I only get one copy.

It's not Hardjono's fault.  It's not mine either.  We're not the owners, 
just participants!  As far as I understand it, the landlord is Mark 
Rosenstein (mar at actwin_com), and the manager is Shaji (who I'm sure knows 
about multiple copies).  My big question is, if you poke around the 
archives, it shows my message of last Saturday being repeated ten times.  
Since my mail got knocked out Saturday morning, I don't know if this is 
really what happened.  I hope not.

> From: Eric Schoville <schovill at expert_cc.purdue.edu>
> Which type of sand should I use for my aquarium.  There are three
> types that I know of, Silica sand, Crushed coral or beach sand, and
> the Play sand that they sell at hardware stores.  Alternatively I could
> collect some form a local creek.  

Silica sand: cheap, available, works.  Don't use if you want to keep 
corys or other bottom-feeders because the sand (essentially tiny glass 
shards!) will shear off their barbels.

Crushed coral: Don't use unless you want high hardness and pH.  coral
contains Calcium Carbonate, which leaches into the water.

Play sand: probably too small to be practical.  But cheap.

River sand/gravel: Always a good option.  Make sure to 
wash/boil/sanitize/whatever before using with your prize fish!

> Also, which fertilizers should I use in the substrate.  Is there an 
> inexpensive source for Laterite, or do people recommend that I put
> a layer of potting soil beneath the sand.

You might try any iron-containing clay as an alternative for laterite
(this is what I do).  As far as I know, there is no cheap laterite, only 
expensive and free.

Potting soil has been used by some, though it doesn't actually contain 
many nutrients (potting soil is mostly peat) and gets used up after 6
months to a year, requiring total teardown.  Potting soil also has a 
tendency to go anaerobic very quickly.

> From: "shaji (s.) bhaskar" <bhaskar at bnr_ca>
> Subject: What's this plant? 
> Yesterday I found a plant that I cannot identify.  I have seen it a
> couple of times before.  The general appearance is like that of
> Didiplis diandra (same size, same kind of leaves, etc.), but the
> leaves are a bright red.  It was beging sold as a species of Rotala,
> but it is definitely not R. rotundifolia, R. macarandra or R.
> wallichii.

How about Amania gracilis?  We got four of those from Mike T for our auction
a couple months ago.  I would have sworn they were Rotala, but they
weren't.  They're sort of growing in my tank, but really want more light.

> From: "shaji (s.) bhaskar" <bhaskar at bnr_ca>
> Subject: Substrate heating coils 
> I finally broke down and decided to try DIY substrate heating. 
> I've decided on a 24V, 2A transformer, and 30 gauge wire-wrapping
> wire, both from Radio Shack.  The only major problem is that I need
> 200 feet of wire to get 30 watts of power.  I'm going to do this using
> 4 reels of 50-foot wire, wound in parallel on a frame built of solid
> steel-core, vinyl-insulated clothesline from my local hardware store.

Won't the steel core rust?  That vinyl insulation ain't too waterproof 
once you get a little cut.  And it cuts easily.

> screwdrivers, and cutting pliers, all things I already have.  
> I expect the total cost of the installed heater to be under $50.
> Any suggestions/comments?

Hmm.  I still think the wire-wrap wire is too fragile and brittle for 
such a task, and the amount of work it's going to take you to wrap 200 
feet of wire around the core (I assume this is some sort of rack?)
is probably worth more than it'll cost to buy the Dupla cable.
But I want to hear how this comes out because I haven't 
heard any "after" stories with 100% DIY setups yet.  I wonder how 
hard it'd be to find out where dupla gets their flexible resistive wire,
and just invest in a spool of 100 or 1000 feet...  Or if we could 
somehow insulate nichrome wire, it only costs a few pennies a foot at the 
Chem supply.

    - Erik

Erik D. Olson                		If mail to me fails, try sending to
olson at phys_washington.edu             	erik at marge_phys.washington.edu