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
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%
and there are other things the vendor will give if you ask but that gets
most of the stuff.
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
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.