Re: Oxygen diffusion vs. nutrient diffusion

> From: Stephen.Pushak at hcsd_hac.com
> This point should be clarified; the Fe in laterite is insoluble and
> bound by oxygen. IMHO it does not represent a sufficient source of Fe.

When a laterite tank is first set up, there are high iron levels, so
all the iron is not bound that tightly.  Also, the anoxic properties
of the substrate will reduce some of the bound iron to the divalent
state. This is good, because the nitrifying bacteria also require lots
of iron when they are forming their colonies.

> The big benefit from what I read is that
> the iron oxides tend to bind up phosphates and tends to fix the
> phosphorous atoms where they don't foster algae growth.
> Do you concur George?

Yes, that is *one* of the benefits. 

> Please note that hence forth I will always make a distinction between
> Duplarit-G which is granules and lateritic clays or fine powder clays
> of all types.


> I don't think it would ever hurt to have heating cables too but
> since George at one point in his career didn't use 'em I'm interested
> to hear if he and Karla were able to quantify any differences upon
> using them?

Well, we went to all the trouble of tearing down the tank without
coils (the 100g "Almost Optimum Aquarium") so we could add some, so
draw a conclusion from that.

Check chapter 9 in the SST saga on the WWW Krib pages: 

    The only differences between this tank and the 100g are the substrate
    heating coils, MH lights and lack of canister filter.  The light
    levels as measured at the surface are about the same (12-15,000 Lux),
    so except for a spectral difference, the lighting is equivalent.  The
    canister filter in the 100g provides extra mechanical filtration and,
    since it isn't cleaned as often as it should, probably acts as a
    nitrate source.  As far as I'm concerned, the only substantial
    difference is the substrate heating coils.

    The biological differences between the SST and the AOA and the 85g tank
    are very striking.  The main thing that is noticable is the almost
    total lack of algae.  While the other two tanks always seem on the
    verge of an algae outbreak, the SST seems to supress algae.  We do
    find an occasional strand of thread algae and the anubias get a little
    red algae, but other than that, it's algae free.  Even the glass stays
    much cleaner.

    [many details deleted]

> a follower of the prophets Horst and Koehler.

Koehler?  Don't you mean Kipper?  Koehler is the toilet guy.

> Re: Aponogeton mad. has small leaves
> George, seems to me you commented you hadn't had success with this
> specimen even using the high-tech approach. *sigh*

We had one that did great for 6-9 months (check out the latest 90g
tank photo in the Krib).  It started to go dormant, so we chucked it.