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Re: Neil's red horemanii

At 03:48 AM 7/3/98 -0400, you wrote:
>fwit I also have one of Neil's red horemanii. Many of the older leaves
>have kept much of the pure dark maroon color but some, that were perhaps
>shaded by other plants now have a slight dark green sheen to them. 
FWIW, my comments about the effects of light intensity and spectrum on
horemanii(red)'s and other plant's color, size or shape are mostly
speculative at this point. 

*The triphosphur Triton light is rich in blue and red. When it passes thru
other (presumably green) leaves which were previously shading the
horemanii, much of the blue and green light is absorbed leaving a light
much richer in red (700-800nm). Far red is reduced the least, so if the
bulb produces any, the red to far red ratio would also be lower. This is
the tree canopy effect.

>After trimming back most of the plants in the tank that were partially
>shading the horemanii, the new growth is coming in a very brilliant,
>deep red. 

Now the plant may not only be getting more light, but one that is much
richer in the short wavelengths (blue and green). I speculate that red
plants utilize these spectrum more efficiently than green plants and there
fore be more important at certain intensity.

>The new growth is also wider and wavier than the older,
>narrower, straighter, dark maroon leaves. 

The change in leaf width and appearance is possibly another response to the
change in light spectrum. Other aquarists have also reported my horemanii
leaves getting wider under triton light. FWIW, my horemanii leaves are
definitely narrower in my tank with a relatively lower amount of blue and
red light.
When comparing the leaf shape of horemanii, it would be best if we mention
if you have one of my clones. . I got mine from Gasser in 1990. I have seen
some other U.S. nursery grown plants with the name red horemanii which are
a different 'variety' of Echinodorus. The new species "group name" for
horemanii is uruguayensis. These plants hail from Argentina, Uruguay and
Chile, with different leaf width depending on location. So, some will
always be narrower than others. [If anyone wants one of mine, email me
after the summer when the weather is better for shipping. The tank needs a
major trimming]
>For comparison purposes: the plant is in a 33 gal. tank with 3 20w
>tritons, laterite substrate, dupla drops and tabs (1/3 to 1/2
>recommended dosage), 85 deg. soft, acidic water, 15 to 20 mg/l co2. 
>Tank houses a couple of adolescent discus so it is heavily fed.  10%
>water changed daily.

To compare light intensity, we really need to know the volume and surface
area of the tank. [Eric- have you updated your study results. We should use
your graph as a reference for comparing lighting]. 

From the discussion above, we also need to differentiate among bulb types /
spectra for the same wattage. And, use/non-use of a glass cover. All of my
tanks are open, which provide at least 10 % more light. This can be
important for people like George, who may be "on the edge." Sorry, I
couldn't resist <g> 

For horemanii, temp is probably important. It prefers cooler water: 70's
better than 80's.  This 'may' be somewhat related to lighting, since plants
do need more energy (light and food) at higher temps.  So the light per
"unit X" statistics should also reflect temp. Eric: can you factor this in

Echinodorus are heavy feeders. I have stunted mine when it did not have
sufficient nitrogen. This will also cause the outer leaves to die. Properly
feed, a sword plant will not loose its outer leaves. This is great for the
lazy aquarist like me who does not like to trim. This should not be a
problem in the discus tank.  A mature red horemanii with perfect outer
leaves is an outstanding picture. But not as outstanding as a tank full of
Karen: does any of your AF  "Aquatic Horticulture" pages show my horemanii