Re: Aquatic Plants Digest V1 #333

>From: krandall at world_std.com (Karen A Randall)
>Date: Thu, 14 Mar 1996 22:51:36 -0500
>Subject: Books, UGF/Heater, Advice, APD, Trace Element Sup's


>Place a UGF plate in the bottom of the tank.  If you are using a 
>fine substrate that might fall through the plate, wrap it in 
>fiberglass screening first. (I use monofilament fishing line to 
>"sew" the screen around mine) Put the riser tubes in place, and 
>put your substrate on top of the plates.  Now comes the biggest 
>difference between this system and a standard UGF.  Instead of 
>placing airstones or power heads in the risers, drop a 7.5W 
>submersible non-thermostatic down each one. (I use 2 in a 55G 
>The warm water rising in the tubes moves water _very_ slowly 
>through the substrate.  Remember that the purpose is to warm the 
>substrate and bring nutrients down into it.  it can _not_ be 
>expected to serve the function of an under gravel _filter_ when 
>run in this manner.

I think this is a great idea. 

I don't like using a soil and gravel for my substrate because everytime I
pull up a plant, a cloud of murk will come out together with the plant
roots, so I prefer a pure fine sand substrate. The problem with this sterile
substrate  is that it becomes difficult to feed the root feeding plants (I
can't find pond lily tablets in Singapore). I will try out this method the
next chance I get.

However, I can think of 2 drawbacks of using a slow flow UGF (as described
1.      all substrate MAY become aerobic.
2.      soil/loam/vermiculite/whatever substrate cannot be used
because it has a tendency to cloud the water.

So, instead of placing a UGF plate directly on the tank bottom, what if a
the UGF plate is placed above a layer of substrate (sand or soil). This
method should allow some roots (above the UGF plate)to get warmed and lots
of water borne nutrients, and other roots (under the plate) to get at
anaerobic conditions and if some folks like it, soil/loam/whatever. Of
course, this would require  a kind of UGF equipment that allows plant roots
to reach below them.

mmm...just my 2 cents worth.

in Singapore with 33 degree celcius heat in the shade,
and 90% humidity.