Most stem plants will send out side roots at leaf nodes particularly, but
not necessarily, if a leaf drops. In natural systems, as sediments
accumulate, the lower leaves rot, roots emerge from their nodes, and the
base of the plant continuously moves upward.

Stem plants are really best suited for moderately-high to high lighting, say
3wpg or better. At those levels, with CO2 injection, they are being pruned,
lopped and replanted so often that side roots don't really have time to
become unsightly.

kush

François Arsenault wrote in message
. ..
Hello everyone,

One thing I don't like about keeping natural plants in my aquarium is that
some species tend to grow side roots on their stems, usually at the base
of
the leaves (or is it where the stems branch?) For instance, plants like
Cabomba (sp?), Hygrophila polypermis and Hydrocotyle leucocephala tend to
do
this in my aquarium. The result can be very messy and unattractive. Can
this
be avoided?

Now, I realize the plants aren't doing this just to **** me off. They must
need them for some reason. But I'm wondering if this is a normal
phenomenon
that can't be helped or if it's the plants' way of compensating for
something they're not getting enough of.

I recently started injecting CO2 into my water, so I don't think that's
going to be a problem. I also add iron-based fertilizer at night once a
week. But there's one component that I know my aquarium is lacking: light.
It's a 40-gallon tank, with a large surface area (36"x18"). But I only
have
one fluorescent light, with a PowerGlo tube. Well, actually, I also use my
old 10-gallon aquarium light at the back, which adds a bit of light
through
the narrow slit that isn't covered there, but it doesn't seem like a lot
to
me. With the surface area I have I assume my plants really need a second
main fluorescent light to thrive.

Anyway, I'm wondering if lack of light can explain the side roots. It
doesn't seem quite right to me, because why would plants need roots to
capture light energy? Don't the leaves do that? But what else can they be
missing that's responsible for this? Unless it's a perfectly normal thing
for the plants even under optimal conditions. But if so, why don't I see
such ugly roots in pictures of healthy planted aquariums?

In any case, I intend to build a cover with two fluorescent tubes in the
near future. I'm sure the plants will benefit from this, possibly even
gaining the upper hand against the algae (my aquarium isn't terrible in
that
way, but it has seen better days). What combination of tubes would be
appropriate? I've read that PowerGlo, while pretty good for plants and for
strong light (which I need to compensate for the lack of a second bulb),
tends to promote algae growth. With a two-tube setup, would it be better
to
add a Aqua/Flora/Life-Glo instead of a second Power-Glo? Or maybe ditch
the
Power-Glo entirely and use something else? I want decent lighting that
looks
nice, is good for the plants and won't promote algae too much.

Thank you for your help.

Francois