Re: 5 questions

[Thomas Barr <tcbiii at earthlink_net>]

> 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?

Not really.
The plant grows well and seems mighty suited to me. It likes lots of light,
CO2 and NO3.  
 
> 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?

No problem growing these.

>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).

Tropica's site etc.

> 
> 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?

Why would you do this in the first place?

Generally folks have trouble with fish disease due to over feeding/stocking,
not doing water changes/maintenance. Controlling this is also good and
recommended for plants.

I have not heard any problems personally from any of these.
  
> 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.

Yes, you can use this. But again, why? Want to feed those sewer worms to
your Discus? There are other ways that are cheaper and easier, good varied
frozen foods/live brine.
 
> 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).

Well there's your reason for the medications.
Lower the fish load/get a bigger tank. Reduce feedings. Add CO2. Add more
algae eaters. 

The pH and KH/GH don't add up. If there was a fair amount of peat etc in the
water, it would reduce the KH/GH and perhaps skew the CO2 level. I find it
unlikely that you have 19-20ppm of CO2 in your tank without adding it at
GH10/KH11. Something is not right there(test kit etc).
 
Red cabomba is easy to grow and fast growing. I grew it fine a 2w/gal.

> 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?

The CO2 is your problem as far as plant needs, but reducing the bio load
will help also/or doing 2x a week water changes(40-50%).

 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?

No. You need CO2 before _anything_ else. This will give you the greatest
improvement. Adding more light without doing this will give you algae. Don't
add the light now and wait and see if you need CO2.

Regards, 
Tom Barr
 
> Thank you in response for any responses, I will certainly appreciate them.
> 
> Regards,
> Brian Rippon