Soils & Lights

> From: RTalukdar at mail_utexas.edu (Roni Talukdar)
> Date: Sun, 24 Mar 1996 17:56:11 -0600
> I'm setting up my 100 gallon for plants in the near future and with
> the recent posts on soils as a substrate, I was wondering what you think
> about my proposed substrate
>         Small (1/2 inch) layer of gravel
>         1-1 1/2 inch layer of laterite mixed with vermiculite
>         1 1/2 inch layer of earthworm castings
>         1 1/2 inch layer of gravel

Given that good growth is easily obtainable with laterite OR
vermiculite OR earthworm castings OR soil, I think you have gone a bit
overboard in trying to provide a "rich" substrate. 

Also, the careful layering that you describe will soon be homogenous
as you plant and replant (a plant tank with optimal growth will
require serious pruning and replanting about every two weeks).  As
some of the components get to the top of the substrate, you may find
that they will cloud the water or begin to get unsightly. 

I think you would be better off to make a simpler substrate and apply
more effort to other things such as water circulation and fertilizing.

George in Sunny Colorado