Re: plant filtration

[Erik Olson <eriko@wrq.com>]

On Tue, 17 Feb 1998, Frauley/Elson wrote:

> Question: does the high rate of flow from the Aquaclear 300 give the
> plant a chance to filter properly? 

Depends on what kind of filtration.  The plants are able to extract
nutrients from the water column, which is what I'm talking about.

> > Interestingly, for Apisto tanks, we seem to have good luck by simply
> > growing *floating* plants with higher light (2 wpg?).
> 
> By floating plants, are we talking riccia, hornwort, etc?

Well, *I'm* talking about Salvinia (floating fern), Limnobium (frogbit),
duckweed, etc.  Stuff that has the roots in the water and rest of the
plant above water.  These are able to grow faster & absorb much more
nitrate and other nutrients than their submerged brethren, because they
get CO2 from the atmosphere instead of the water (a limiting factor when
you're not a yucky plant person injecting CO2 into the water). 

For example, my tank at work seems to double its mass of Salvinia every
few weeks.  Instead of changing the water, I yank out half the plants.

> I don't think a dangling
> terrestrial plant would outcompete submerse plants, would it? 

If the dangling plant had enough mass, yes, it could.  But in general, if
there's enough nutrients and light for both, they can co-exist.

> By the way, I'm not going to the plant list with this because I see it
> as a possibly eye-pleasing approach to good apisto-level water quality.

Right, those nutty plant people would probably flame us for thinking
of wasting that valuable light energy and fertilizer on emergent floating
plants.  :)

  - Erik

PS, ObApisto:  Anyone ever heard of A. norberti II ?  We saw a pair in a
store this evening.  I won't mention the cool plants we also saw.

- ---
Erik D. Olson					         amazingly, at home
eriko@wrq.com