What's the dirt on dirt?

["Ellen O'Connell" <oconnel4 at ix_netcom.com>]

 >Actually soil. Is anybody using it? I have been reading Walstad's treatise
 >on the planted aquarium, and I was wondering if anyone has used and tested
 >her theories extensively.

I don't qualify as having tested extensively, but I read her book last year 
and set up my first soil substrate tank just over a year ago, a little 
mini-bow for my office desk that I didn't want to have to fuss over or have 
too much extra stuff around.  The tank does not get sunlight in the office 
and has exactly 2 watts per gallon of regular flourescent light.  I did run 
some DIY yeast to it in the beginning.

Everything about this little tank has been a joy.  It's never had any algae 
until lately, when a little green spot has shown up on the glass.  It has 6 
white clouds in it that I got as 1-inch babies and that are now full grown 
2 inchers.  It's never had any algae eaters except some snails that snuck 
in on plants.  It's been so successful that I've been changing over all my 
home tanks to soil substrates.  A 10-gallon also worked well for probably 
six months until I tore plants out of it helter skelter and brought up 
masses of dirt from under the substrate, thinking I was giving up that 
tank. Then when I changed my mind, I scooped the top off the mess, put more 
gravel over the top and started it up again.  It's only been up maybe 6 
weeks and has 3 watts per gallon regular flourescent and some sun where it 
sits on the kitchen counter.  It has some diatom algae right now.  My third 
soil substrate tank is a is a 28-gallon bowfront that has been up in my 
bedroom for about six months and has been equally successful as the little 
tank at work.  It gets a little sun, definitely less than Walstad talks 
about and through one end.  It has 2.3 watts of compact flourescent light, 
which seemed too much, so I positioned the light so the black plastic that 
keeps the 2 parts of the glass cover together blocked part of that light 
(CF light is much more light than regular flourescents, more so than I 
expected).  I am about to convert my first tank, a 20-gallon long to soil 
as soon as I get up the umph to clean out the gravel and laterite that's 
there now.

The only hard part of setting up these tanks was finding a soil to 
use.  Soil from where I live in Colorado is nothing I would put in an 
aquarium and I went around and read the contents on potting soil for sale 
in stores for weeks before finding an old fashioned kind of hardware store 
that sold some plainish potting soil without fertlizer, chemicals, 
earthworm castings, etc., in it.

As to maintenance, the hard part is accepting you can't plant a lot of stem 
plants and keep uprooting them to rearrange or top them.  Even so, you have 
to start with some fast growers.  I use stems that don't have too extensive 
of roots, limno is working well, and am more and more using crypts and 
small swords.  When I started the tanks floated something like anacharis or 
hornwort in them, and they all have a bit of duckweed on the top I have to 
keep after.  I've also acquired a wide mouth vacuum that helps clean up 
some of the dirt off the top of the gravel when it's necessary.


Dirt or no dirt, each of these tanks is different because of the 
light.  The 7-gallon with its 2 watts per gallon grows dwarf sag very 
slowly.  It's dark green and about 2 inches high.  When I planted a bunch 
of it in the front of the 28-gallon with the CF light, I expected it to do 
the same thing, and instead it grew fast, more like 8 inches high and was 
much lighter green.  Java fern was puny in the 7-gallon and I thought 
because there are no nutrients added to the water it wouldn't grow in this 
setup, but it's flourishing wildly in the 28-gallon, and java moss is doing 
well in all 3 tanks.

One thing that I have not experienced that Walstad talks about it ph 
stabilizing at about neutral.  My water is pretty hard (I take my well 
water to the office tank rather than mess with Denver water) and I mix it 
50-50 with R/O water.  Ph stays at about 7.6 without CO2.

Hope that helps.





Ellen O'Connell
Parker, CO
mailto:oconnel4 at ix_netcom.com
http://www.rottrescue.com/