Patty:

Didn't want to get in trouble for straying too far from the main stream,
and getting in trouble with the "powers to be", especially since people
don't hear much from me due to my declining health.  However, sometimes
where I think I can really contribute I will break through the drug
barriers and contribute.

I have had an invertebrate coral reef tank now for over 2 years.  The kids
gave me the money for the tank and stand Christmas two years ago, and I
hate to think what I have invested in it since then.  Have learned a lot,
from trial and error and especially reading.

There are basically two ways of going on tanks, either natural-type systems
or tanks using mechanical equipment to keep the water quality in good shape
(I am assuming that you do not have access to fresh natural seawater on a
daily or so basis as I do in the SW USA high desert).  I choose the natural
system because it is probably harder, but does not require as much
bioengineering.

Basically you want a system that will provide the nutrients that your
inhabitants need to grow (e.g., Ca, Sr and carbonate for the shell and the
food for the animal doing the shell production) and get rid of the waste
products so that they are not poisoned by their own wastes (e.g., too much
excess organics, nitrates, heavy metals, etc.).  A natural or mechanical
system will provide both but a slight hybrid of the two seems best.  I
would recommend the modified natural system since once set up it requires
less maintenance (but constant watching) and costs less (in my opinion).

You are a book seller, so this might be easier for you.  I would recommend
a couple of little books (cheap, less than $10 US each) to read on how to
set a natural system up:

"Live Sand Secrets", 2nd edition by Dr. Bob Goemans and his new booklet
(the live sand reduces the nitrates to nitrogen gas)
"Protein Skimming and Activated Charcoal Secrets" (get rid of excess
organics and heavy metals).

They are published by Marc Weiss Companies, Inc. (Florida) - Fax -
954-894-9226 (I cannot locate an email address).

These will give you an idea of what is ahead.   If fish stores are rare
where you are, look for one of the e-commerce pet supply shops on the net
in Australia that specializes in marine fish/invertebrates.  They should
have them.

Paul (see below for more info)

At 02:48 PM 5/2/00 +1000, you wrote:
>Dear all,
>
>Please don't discuss requirements for keeping cowries off-list! I want to
>set up an aquarium with live C. caputserpentis and C. annulus (and whatever
>else I can find locally) soon. I was quite intrigued by your mentioning the
>requirement of shell-building materials.

You want aragonite (crushed coral and shells other than oysters and a few
others that have calcite shells; and/or oolitic sands which occur from up
welling of deep cold carbonate-rich seawater and you get inorganic
precipitation of aragonite - e.g. the Bahamas Banks.)  You do not want any
kind of fossil material since aragonite converts to calcite very quickly.
The beauty of an aragonitic substrate is that it is thermodynamically
unstable in seawater and tends to dissolve to keep a constant concentration
(and supply) of Ca and carbonate in the water without adding these as
additives.  If you have a quartz sand substrate then you have to add the Ca
to the water and monitor it closely to make sure what the concentration is
in the seawater all the time (the carbonate, as carbon dioxide, is free
from the atmosphere).

 Is there another substitute? The
>pet stores around here don't even sell decent freswater plants, let alone
>specialised minerals!

Even here in the high desert of the USA most pet stores have some marine
fish/invertebrates and sell bags of the aragonitic materials.  Look around,
I am not sure how remote you are.  If not, I am sure you can find it
locally on the WWW.

 Where do the cowries get the stuff in the wild?

They get it from the seawater which is constantly renewed.

 Could
>I use coral sand (I've seen that for sale in the shops) instead?

YES, YES, JUST MAKE SURE THAT IT SAYS ARAGONITIC SAND ON IT!!!
>
>Patty
>

There are plenty of more expensive books, but these two should give you an
idea.  There is a American publication that specializes in marine subjects
(Marine Fish Monthly).  Over half their articles are on relevant issues to
invertebrates since "reef" aquariums are so popular now.  Good articles,
minimal articles and they have an email address (editor and publisher):
[log in to unmask]  For those of you in the U.S., it can be found in most
bookstores.

Sorry, probably more than you wanted.  Before you set up a system, decided
what you want to keep in your system.  If it is just algae-eating Cypraeas,
then you can let the algae grow wild and they will love it.  If you want
corals, it's a totally different kind of commitment.

Paul


>P.S. Thanks for replies on Marginellas - more to come
>WWW: http://www.capricornica.com
>
>Capricornica Publications               on-line natural history bookshop
>P.O. Box 345
>Lindfield NSW 2070
>Australia
>
>phone/fax: 02 9415 8098 international: +61 2 9415 8098
>mobile 0412 865030
>
>E-mail: [log in to unmask]
>
>