Specifics.

[DandelionSea at aol_com]

People of THE LIST,

I have a few questions regarding specific aquatic plants that perhaps can 
only be answered by the gurus of the aquatic gardening world.

First of all--I would like a little information on Bacopa lanigera.  
Kasselman calls it (paraphrased) "ill-suited to or not at all appropriate for aquarium 
cultivation".  Is there a secret to making it grow submersed, or is this a 
terrestrial/marsh plant that does not exhibit a submersed habit (other than 
rotting)?  I have access to both the variegated and green morphs.  Is one more 
suited to submersed life than the other?

Second of all, I haven't been able to find a comprehensive guide to Ludwigia 
species that displays all (or most) known species/forms that are suitable for 
aquaculture.  L. repens and its immediate hybrids are obvious enough, but what 
does glandulosa look like emersed, or for that matter, palustris?  The shops 
around here all get in weird Ludwigia from time to time...repens emersed blade 
shape with pink stem...palustris blade shape with red veins...etc.  I would 
guess that since most of the time I find repens in emersed foliage that these 
too are grown emersed.  I suppose my question is this--is there a resource on 
the internet or in an easily accessible book that I could use to get definitive 
identification of Ludwigia species?  Any help at all would be appreciated.  
(By the way, the Kasselman book is fairly useful, but it tends to give only 
pictures of submersed specimens, and lists only the most basic of the hybrids).

Third, does antibiotic medication (i.e. Spectrogram, Kanacyn or Hex-a-mit 
from Aquatronics) affect plant growth if left in the water for extended periods 
of time?

Fourth, I have access to cheap, available Metronidazole in 250mg tablet form 
intended for canine use.  Does anyone know if this stuff is water-soluble or 
suitable for aquatic use?  I tested one tablet in a cup of tapwater, and it 
desolved in a few hours, letting loose bubbles initially and eventually 
disentegrating entirely.

Fifth (and last) of all:  Cabomba furcata is listed as a "very high light" 
plant, requiring "more light than most aquariums can provide" (paraphrased via 
Tropica).  I have 2.3 WPG of cool white and full spectrum fluorescent light, a 
pH of 7.2, GH 10, dKH 11 and a soil underlayer beneath medium-grade gravel.  
There is no CO2, and most of the fertilizer comes in through the fish food (the 
bioload is very high in this particular tank).  The only chemicals I add are 
a "recommended dose" of Kent Botanica Grow (contains enough K2O, Ca and Mg to 
make the water hard) and a water-soluble Ca, Mg and Zinc supplement in tablet 
form once a week after my water change (about 40-50%).  My question is this:  
Since the C. furcata in my tank has very short internodes, and the leaves are 
quite red/gold (all in all an extremely healthy and robust plant), does this 
imply that the emphasis may be more on the quantity and uptake of nutrients 
than the amount of light, as is thought?  I once knew a guy who had a set up with 
C. furcata, and it wouldn't grow well until he had upwards of 3.5 WPG.  What 
am I doing right?

Thank you in response for any responses, I will certainly appreciate them.

Regards,
Brian Rippon