[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: More light and lots of it

Michael D Nielsen <mnielsen at U_Arizona.EDU> wrote:

> I am thinking of upgrading my lighting on my 29 gallon from 60 watts to
> 150 watts (VHO).  CUrrently I have a semi-experimental substrate of 10% of
> the normal amount of laterite for this size tank mixed in the bottom 1
> inch of blasting sand, 1-2 cups peat above this and capped with 2-3 inches
> plain blasting sand.
> I was wondering if when upgrading the lighting and adding CO2 as well due
> to the higher light levels, if I should change the substrate to something
> more fertile.  My thinking is if I boost the plant growth with more light
> and CO2 should I also help out the root system as well?  Changing  the
> substrate is not a problem.

There are two aspects to substrate fertility: micro nutrients such as
iron, manganese, and so forth and macro nutrients. Since you are
concerned about the suitability of the local soil, to provide macro
nutrients, I suggest that you find some pottery clay and mix fertilizer
(about 10 pellets / tsp) and make these into small balls or pellets.
These can be added selectively to your substrate and are great for
boosting macro nutrients.

If you can find a fertilizer which also contains micro nutrients
(sometimes called trace nutrients or trace elements), you can also use
this with the clay ball approach.
> Last thing.  I live in Tucson AZ and as Steve (?) has pointed out using
> the alkaline soils found in many deserts is not the best of ideas so using
> the go out and dig up a soil is not real feasible.  There is some river
> soil which may be OK, but is very young and of generally poor quality.

I would avoid soils found in salt flats and depressions. I don't know if
there are any geological formations originating from glaciers in
Arizona. The glaciers extended pretty far south. You should be able to
find a lot of information with a little WWW research. Some of the URLs
listed on my web page may be useful. You might find suitable soils on
such formations. Travelling into the mountains might also give you
access to suitable soils. I wouldn't make a special trip but carry a
shovel and pail on the next occasion you make a long car trip. You can
test the soil for alkalinity by putting a sample into a jar of water and
measuring the pH. I would use a larger ratio of peat with an alkaline
soil as this will provide a more ideal pH and the organic materials
absorb large amounts of free metal cations.

Take a look in the local garden centers to see what kind of dirt is
available. I'll bet there are a lot of successful gardens which use
nothing more than local soil probably enriched with peat to lower the pH
which improves micro nutrient availability.

Steve Pushak                              Vancouver, BC, CANADA 

Visit "Steve's Aquatic Page"      http://home.infinet.net/teban/
 for LOTS of pics, tips and links for aquatic gardening!!!