Laterite - the whole story

I hope you all appreciate the fact that I'm very lazy and don't like 
being bothered by having to make this entry but hopefully it will be my 
last post on the subject.

What is laterite?  A high iron clay formed in tropical areas.  Most of 
commerical laterite is mined from the US in areas that were tropical 200 
million years ago.  Where I live in northern Mich we have Petoskey stones 
formed 260 million years ago (they are focillized coral) which further 
proves this area was once tropical.  At any rate, you don't have to be in 
the tropics to get laterite.  Georga red clay may be a type of laterite 
for all I know but since it is not a normal source the Fe content is 
probably low.

Why is it so expensive?  Packaging, shipping and commercial greed!  Think 
about it - if you had the market cornered (for aquaria) how much money 
could you make.  A.  Not that much really since there aren't that many 
people out there that want to bother with substrate heating etc.  The 
authors of THe Optimum Aquarium did a fantastic job of isolating all the 
things that guarentee success and it is only natural they expect to be 
paid for their research.  In a sence I am being very unethical to suggest 
lower cost alternatives but then people are doing DIY co2 yeast units, 
alternate substrate heating - etc.  It is important to know why you are 
doing something so I suggest before anybody jumps into this they read TOA 

Chemical breakdown. - got it for "red art clay" but don't have a clue 
what Dupla's is.  It would be nice to get a post from somebody who 
analyzes Dupla.   I suspect it will be close to red art clay.  Even if 
the Dupla stuff is higher in Fe that means we might use a little more of 
the almost free stuff. (A package of Dupla works out to about $50 a 
pound). Chemical analysis:	SiO2 	64.27%
				AlO3	16.41%
				Fe2O3	 7.04
				TiO2	 1.06
				CaO	  .23
				K2O	 4.07
				MgOO	 1.55
				T2O5	  .17
and there are other things the vendor will give if you ask but that gets 
most of the stuff.

Source?  A.R.T.
	 1555 Louis Ave
	 Elk Grove Village, Il 60007-2313  Phone 1-800-323-0212
 or 708-593-606.   Ask for Chuck ( talked to him this morning and warned 
him he may get a call or two).

Cost $$$?   	50#	$11.00
		25#   available but I forgot to ask price
		 5#	  3.00
Catch - minimum order is $30 or there is a $5 handling charge.  Shipping 
by UPS is, or course, extra.

Remarket through this plant list?  Good idea and I wanted to do it, but 
like I have said before, I am not a type A person like when I worked for 
GM so I don't want to be bothered.  Dupla sells the powder and 
"pellets".  At one time the fellow who is the potter and I talked about 
marketing this stuff and would have mixed up a batch of clay and run it 
through the extruder he has.  We would then cut off hunks similar to 
Dupla that would be about the size of a marble.  FIRING THESE CHUNKS 
WOULD DEFEAT THE PURPOSE OF THE LATERITE.  It has been suggested we could 
get laterite in our tanks by breaking up clay pots.  The stuff used for 
clay pots has very little iron and I suspect firing bonds the stuff 
together in a way that would be of little use to plants.
I have seen no evidence that the clay chunks are of any real value.  They 
do hold up well and are easy to form from the powdered laterite from 
Duply or A.R.T.  If you work with this stuff you will find it takes very 
little water and that the result is very sticky goo but it is easy to 
make up the marbles.  Would be a great project for a fish club.

Other Sources - Rouin Ceramics
		15333 Racho Rd
		Taylor, Mi  48180  phone 313-474-0010. (I did not talk to 
them and figure my phone bill is big enough).

  other other sources ---probably a bunch.  Check your local potter and 
work with him/her.  You will find the analysis of all these clays is not 
secret and you can compare.  Obviously you want the highest Fe content 
you can get.  To carry this to an extreme it would be interesting if 
somebody put a sheet of soft iron sheet metal in the bottom of their 
tank.  That way you would be at near 100%.  The process involved in 
plants taking up iron is very complex and beyond my limited education but 
I am smart enough to know the answer is fairly complex.  I do know that 
with either the Dupla or "cheap" laterite that the Fe test does not show 
a high iron content from just using laterite.  It is still necessary to 
use liquid fertilizers.  

What's next?  For me, nothing - I'm going back to play with the fish.
The profit is not going to be fantastic so this will be a labor of love 
but I hope through the postings that agreement can be reached on how to 
do it for the most good to the most people.

How much laterite do you need for a tank?  Tables have been published 
here from TOA.	For gallons divide liters by 4 and you will be close enough.
Tank size in liters  in gallons 	grams laterite   lbs laterite
110			25			250	  1/2
200			50			500	  l  (454g/lb)
350			87		       1000       2
520		       130		       1500       3

On page55 of TOA I read "The iron contaiing additive is mixed with the 
actual substrate used in a ratio of approximately 1 to 3 before it is 
placed in the aquarium, and the mix thus prepared makes up the bottom 
layer of the substrate.  This is then covered up with the balance of the 
substrate ...".  I took this litereally before I studied the table given 
above and ended up with many times the table value.  I would guess 
laterite has a specific gravity of close to 2 so either by volume or 
weight the 1/3 of 1/3 would give close to 10% by weight or volume of the 
total substrate.  A good rule of thumb is 2# of gravel for every gal of 
tank size which would make the 130 gallon tank above have about 250 
pounds of gravel and mixed in the bottom 1/3 would be over 20 pounds of 
laterite!  At Duplas price of $50 per pound that would be a chunk of 
change.  I did this in a 230 gallon tank (used about 35# of laterite) but 
that is the subject for another posting.

So much for now.  Go ahead you entrepenuers (never could spell), go 
ahead and save everybody the inconvenience of having to get a minimum 
order from the souce.