Laterite clouding and 230g update
A little slow in talking about this even though there were several posts
re clouding (Thanks, Phillip).
Case 1. Not having the benefit of this list and the access to "The
George" (Boothe) - I thought a good way to get laterite into the
substrate was to mix it with the bottom 1/3 gravel and put it over an UG
filter plate. I used Dupla powder laterite in a 100 gal tank. Instant
mud! It looked like one of those high silt river runnoffs with initail
visibility of about 1" After a week it was closer to 8" of visibility so
it was obvious the tiny clay particles were attatching themselves
somewhere. In a few weeks the tank was crystal clear. Gravel vacuuming
always showed evidence of laterite in the vacuumed gravel. BTW - tank
had MH lites and Dupla co2. Great plant growth.
Case 2. Wife let me get 230 gal so I tore down the 100 and set 230 in
same spot. (72x24x30hi inches). Since setting up the original tank I had
the benefit of reading G. Boothe's article in AFM re substrate heating
advantages and why ugf is no good with laterite. Also had built a few
DIY UGHeater systems. So the 230 was set up with 1/2 of the tank with
ugheater and laterite. Other half was ugf with 230 gph power heads (2
plates and power heads). Due to a missunderstanding in reading TOA, I
used about 10x the recommended amount of laterite. This was the cheap
pottery stuff described in previous posts. The laterite was mixed with
wet gravel and the resultant bottom layer of substrate looked fairly
dry. I carefully added non treated gravel over the filter plates and
then very slowly filled the tank.
When using a gravel vacuum I like to go deep - all the way to the
I placed a piece of egg crate light diffuser grid over the laterite rich
bottom to protect the laterite from being sucked up in vacuuming.
When the power heads were turned on they immediately spewed forth clouds
of laterite but not as bad as the case 1 tank. Nuts - somehow the
laterite had crept into the other side past the plexiglas barrier I had
placed in the gravel. At any rate the cloudiness dimminished fairly
quick compared to the case 1 tank. I was always able to see to the back
of the tank although very cloudy.
Case 2.1 - - DISASTER After being set up for 6 months the tank developed
a leak. AFM magazine came the day I discovered the leak and there was an
excellent article on how to fix a leak. Good timing. At least I'm not
the only one who ever had a leaky tank.
Teardown was time consuming but straight forward. The grid allowed me to
strip off all the regular gravel and save the laterite gravel without any
Interesting observations- - the plants did very well on both sides of the
barrier but some val grew noticeably faster on the laterite side. The
ugh was on very little due to the warm weather. On teardown the ugf side
had considerable laterite in the gravel. When I washed the gravel it had
the rusty mud color. Also, the bottom of the filter plates were stained
with clay that had been in suspension and then adhered to the plate.
Roots had penetrated all the way under the filter plates and in a few
cases on the laterite side there were roots deep into the substrate. The
substrate looked very dense with so much clay but there was no obvious
organic material or smell etc to indicate anerobic status.
Case 3. Finally got the tank set up yesterday with slight differences
from the original. The clay rich section was less moist. When clay
sticks to gravel and is not disturbed, it tends to stay put. The tank
was filled and when the ugf power heads were turned on there was almost
no cloudiness. After 36 hours of operation the tank is crystal clear.
Forgot to mention the gravel is about 6" deep so the roots going all the
way to the bottom of the tank raises a question of just how far they
would go if left to a bottomless base. Hopefully the laterite migration
into the ugf side will be nil and that we can see a more significant
difference between the two sides. The earlier pass with the large amount
of laterite in the ugf side indicates the laterite was available to both
sides so it is not surprising there was little difference.
Hopefully the tank will not leak and we will have enough time to report
significant diffrences at some future time. The conclusion I would reach
at this point is that laterite will cloud a tank if too much water is
used when mixing it in the gravel. The less the better. And even if it
does get into suspension it will eventually clear by adhereing to
everything it comes in contact with.
Sorry for the long post but hope this will be of interest to some of you