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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 
bottom. 
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 
contamination.  

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 
out there.