Oh. I just finished getting myself disentangled from this thread the other
day. I seem to be becoming the official board UGF advocate.

And I never seem to have a problem with roots getting tangled in the plates.

Advantage: stem plants by and large seem to do better in UGF systems because
they are less prone to root rot. Disadvantage: swords and other heavy root
feeders do not do as well because you can't easily use solid fertilizer
tabs/spikes (they melt away quite quickly). I've had poor luck with some
crypts, too.

Advantage: in my experience, I've found it easier to establish and maintain
equilibrium in UGF systems, probably because of the enhanced circulation and
because, using nearly pea-size gravel and being able to flush out under the
plates, you can get things really, really clean, as compared to a
conventional setup.

I like inserting my CO2 bubbles at the bottom of the riser tubes. By the
time the powerhead impeller is done with it, very little of the bubble gets
to the surface.

A UGF system, in theory, does a superior job of filtering because the entire
gravel bed becomes a biologic extension of your mechanical filter.

If you end up using an undergravel filter, I recommend against using
bubbles, at least during the day.

kush

"You can't have everything - where would you put it?"

Cannibul wrote in message
news
On Mon, 9 Dec 2002 23:47:18 -0000, "lynsey"
wrote:

What are the advantages/disadvantages to an undergravel filter?
(especially when growing plants)

Thanx,
Lynsey.



Disadvantage is the roots get tangled in them. Makes it hard to
move plants or remove plants. As far as advantages I can't think of
any that over come the major disadvantage.