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

re: Kevin's substrate

> Steve - I understand what you told me and will adjust my plan accordingly -
> one more question - how much of the micronized iron do i use - i have a
> plastice cup of the stuff that is about "pint size".  Thanks.

I think a cup is probably plenty. I don't think its really critical.

Something George said about not using Discus initially is good advice. I
would say that substrates with peat or soil containing organic material
are all going to go through the transition phase for about 2-3 months.
I'm always cautious with my fish in a new tank.

Something else which concerned me is that people tend to use quite deep
substrates sometimes and this is probably not the way in which Paul K
was using his peat and soil mixtures. I think he was using peat and soil
in the trays because the trays developed iron deficiency after a year or
so. In those trays the soil was only 1/4 or 1/2 inch deep. In that
situation the peat keeps the oxygen level low enough so that iron can be
dissolved. I think that in deeper substrates we should be using much
LESS peat possibly even less than the 5% by weight I am currently using.

The point of using 3 layers instead of 2 is to keep the peat layer small
and to not have organic material deep in the substrate. I know that in
an 8" substrate which is mostly sand that the redox is low enough when I
uproot a large plant that I can smell a little whiff of something
sulfery when I pull it up. The roots on those plants are ok but that's a
signal of how things could potentially go wrong when you don't follow
the directions.

I think laterites and clays without peat are just as good. The peat is
only there in my tanks now to see if I can keep the tanks going WITHOUT
ANY additions of chelated iron or trace nutrients. That's the only
reason the peat is there. If you plan on using PMDD with trace
nutrients, it is probably better not to use peat and to stick with a
mineral soil such as subsoil, clay, KL, laterite or soil-soup. Paul's
soil-soup removes most of the organic material from the soil and I think
Paul mainly uses trays. I don't think KL has much available iron in it
(maybe someone can comment) so it might be good to add iron in some form
with kitty litter.

Sorry for making things complicated. The method described on my page is
designed with a few specific goals in mind. There's several thousand
variations, many simpler in some respects but complicated with test kits
and iron additions. It's so hard to explain the need for a specific
design because of the interaction of oxygen, organic matter and bacteria
in the substrate.