"Boomer" <wcwing@nospamchartermi.net> wrote in message
news:adR%e.3505$ES.2473@fe07.lga...
So lets unconfuse you
The CONFUSED informing the confused. Hmmmmm.


Q1. It will not help keep up the pH, Ca and Alk. It does not dissolve
unless the pH falls,
You are contradicting yourself in the same sentence and you don't even know
it. If the pH falls and CaCO3 dissolves than [Ca++] increases, along with
[CO3--] and [HCO3-]. CaCO3 contributes to your overall buffering capacity.

When the pH drops your substrate i.e. aragonite (a form of CaCO3) breaks
down (dissolves) into Ca++ and CO3-- and adds to your buffering capacity (pH
stabilization).

for x number of reasons. It my add a tad to the pH, Ca and Alk but in a
trivial,
depending.
What?? You just said in the previous sentance that it WILL NOT help keep
up the pH.

In short time it will be coated bacteria and organics and all that will
stop,
unless the pH falls much lower. Do not worry about it.


Q2. Ca and Mg will precip onto some of it initially, if it is aragonite,
less if calcite
and more so it dolomite. However, such Hi-Mg Calcites will just go right
back into
solution. Again in a short time it will get coated with bacteria and
organics and this
will also stop

So don't worry about any of this

Kim said this

"Now if you are trying to run very very high calcium and alk. The CA
will precipatate out of solution"

This has nothing to do with the sand/say but does happen, it is called
abiotic precip, aka
hard water deposits. All tanks have some, like the heaters and at the
water-air interface
and sometimes lower on the glass. On fresh sand it can also happen more
so, as Kim stated,
as the Ca has a greater affinity to be attracted to a similar surface
chemistry. However,
again on the sand, organics and bacteria will stop this once coated.
--
Boomer

Want to talk chemistry ? The Reef Chemistry Forum
http://www.reefcentral.com/vbulletin/index.php

WCWing@nospamChartermi.Net
Former US Army Bomb Technician (EOD)
Member; IABTI, NATEODA, WEODF, ISEE & IPS

If You See Me Running You Better Catch-Up


"Thomas Bartkus" <thomasbartkus@comcast.net> wrote in message
news:pan.2005.10.01.16.55.45.93346@comcast.net...
: Okay - I'm confused.
:
: I *do* want to use calcium carbonate based sand because -
: It will help keep up the calcium & alkalinity & pH & trace elements as
the
: sand slowly dissolves into the water. AND it won't scratch the glass
like
: a silica sand.
:
: I *don't* want to use calcium carbonate based sand because -
: Calcium will preciptate out onto the CaCO3 sand and cause the
: alkalinity and pH to drop. I will have a heck of a time maintaing
calcium
: & pH. Better to use a neutral silica or perhaps aragonite sand.
:
: What to believe?
: Thomas Bartkus
: