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09-02-2004, 09:02 PM

wrote:
Bill Kirkpatrick wrote in message . ..

Principal causes of

BGA are 1) dumb luck and 2) excess nitrates.

Excess NO3?In terms of what?

You're preaching to the choir, perhaps reply to the post
that made the claim. Everyone ends up inoculated with BGA,
and BGA doesn't care about NO3 - it will fix it's own nitrogen.

BGA and most other algae appear when something runs out, rather than
somethuing becoming excessive.

Eh? Life is a constructive process. It frankly doesn't care
if, or when, "something runs out" if it has no biological
use for that particular "something". Thus, BGA, or anything
else, simply cannot grow for LACK of a required component.

PO4 causes BGA?

Ok, "Cause" was too strong. Technically, BGA "causes" BGA.
P only helps it along, and research suggests P is one of
the inputs through which it can be limited.

NO3 is surely not limiting for BGA. But anything that the
higher plants can store can likely be used as a limiter.
Some of the traces, perhaps. Run an iron poor tank, spike
once in a while, just near the point your higher plants show
chlorosis.

P is a good choice because it is a macro. Plants and algae
need "lots" of it, relatively speaking. Thus it might be
considered easier to limit.

That's simply wrong.

Really? You have science to share?

Search the web for PMDD, or "Poor Mans Dupla Drops". Not so
much for the formula, but it's development came from quite a
bit of interesting research regarding algae.

But the assumption made about excesses causing algae is wrong.

Well, let's define excess. Greater than 0. Phosphate is a
required component for life. If you have 0, you have NO
life, none, not at all. BGA, or otherwise.

Sears-Conlin seems to have gone to quite some length to be
so flatly declared "wrong", without, at least, a couple of
dozen pages refuting them in a bit more scientific way.

You are wrong.
Many/most species of algae can store PO4 for up to 100 generations and
survive at far below limiting conditions for plants.

Again, you have any science to share? Look, Algae is a one
cell plant. It grows by fission and spore. How can a spore
possibly collect P from it's parents? Being one celled, and
without a nutrient transfer system, how does P magically
migrate to subsequent fission generations? The cell splits,
roughly 50% of the material is split between two new cells.
Both must now acquire materials to double their size. How
can the ultimate parent possibly, even remotely, "store"
enough PO4 for "100 generations"?

If you maintain 0 Phosphate - algae can't get any.
Oh yes they can.

Really, when is 0 not 0. BGA can fix Nitrogen, when NO3 is
0. But, P? Unless the BGA can crawl out of the tank and
acquire some dirt for themselves, 0 defines "can't get any".

Fish food, and plant leeching is plenty for algae.
They might slow down some, but they will still grow fine, BGA is no
exception.

Then were are not talking 0. You have inputs. If those
inputs are kept below total consumption demand, the inputs
are peaks and will return to zero.

During that non-0 time, algae, BGA and other, will surely
take advantage. So will the higher plants.

BGA has some effective doubling rate. If the P is available
for a short enough period of time, the BGA doesn't have much
time to double. Yes, it will expand, but 1 cell growing to
2, for adequately small random values of 1 and 2, does not
an outbreak make.

Meanwhile, in a P deprived tank, there is little leeching
from the higher plants. They are in acquisition and storage
mode, hungry. They are slower than BGA, to be sure, be
we're back to the small random values of BGA doubling in a
competitive environment, returning P to 0.

If the plant has what it needs to grow well, then it will do well and
the algae will not.

Algae is not a "plant"? Please share the biological
differences are you aware of between "plant" and "algae"
that would account for one "doing well", and the other not,
when adequately offering everything "plants" need?

Plants need far more nutrients relative to biomass than algae.

The point, exactly.

It's like having a mouse and an Elephant and feeding both the same
amount and then deciding to feed less. Which will starve?

Yes, exactly. If you have a mice and an elephant in a
sealed room (tank), and you throw 100 peanuts a day (P) into
the room... The clearly hungry elephant snorts once and the
mice get none. Maybe the elephant's clumsiness leaves the
mouse population 1, or 2, or 10 peanuts. Not enough for
mice to breed as rapidly, or support a large mice population.

Now, feed the room enough peanuts to meet everyone's demand.
They elephant is happy, and the mice breed. Many mice, so
many mice.

I had it(PO4) for decade, I loved it and so did my plants.

P has never done it for me, personally, in any form. Now,
my plants, I'm told, enjoy it immensely.

and good light. And, yea, use

Adding KNO3 regularly will generally cure BGA after you kill it off
first by doing a 3 day blackout, combined with 2 dosings after 50%
water changes right before and right after a blackout. Then regular
routine dosing of KNO3.

Why do you imagine KNO3 helps? KNO3 is 50-0-50 fertilizer.
May I call your attention to the complete lack of P.

Plants don't grow well when they don't have enough GH, CO2, NO3, PO4,
K+, and traces.

BGA fixes its own NO3, so there is no point in limiting
that. All you'll do is deprive your higher plants. Deprive
the higher plants of NO3, and you lower their competition
for P, and everything else.

So, what is PMDD? Well, a N-0-K fert with micro (Ca, Mg,
which is not just GH, btw, you can have high GH as all Mg or
Ca, and none of the other - and dead plants will ensue) and
the trace elements. All needed in proportion. Your routine
use of KN03 is incomplete - unless you are bringing in the
rest in with water changes. But, not everyone's input
waters are complete in this respect. Some use RO, some have
home softeners, some use strong micro-pore carbons to crack
chloramines (and lose metals in the process), some are just
lacking this, or that, in their tap.