I recently bought an eclipse system 12 (acrylic) as it seemed
recommended for a beginner, but am having second thoughts.

Eclipses aren't ideal for planted tanks. It's not easy to upgrade the
lighting, and you don't get to choose a filter, since it comes with one. IOW,
the very things that make it so easy for a beginner limit your options if you
want to do something different...like keep plants. :-)

But the lighting doesn't seem adequate from what
I've read so far (1 watt per gallon).

If you stick with low-light plants, that will be enough.

And I'm wondering about the
filtration being compatible with plants (and the betta).

It will be fine, for a low-light tank. Unless you're injecting CO2, surface
turbulence is a good thing.

However, if you think you might want to upgrade one day -- higher light, CO2
injection, etc. -- then an Eclipse is probably not the best choice. There are
things you can do -- special upgrade kits, removing the biowheel, etc. -- but
you'd have more options with a standard tank.

So far I've been considering some of the following:
Anubias nana
Java moss
java fern (also I've read it needs at least 2 watts/gallon somewhere)

Those plants will be fine in the Eclipse. I've grown them all with less than 1
watt per gallon. And the Eclipse isn't that high a tank, so the plants will be
closer to the light than they would be in, say, a 29 gallon tank.

water sprite (I understand it's fast growing and will take up
nutrients, preventing algae, and that I keep cutting it back till the
other plants get established. But will it grow fast enough in low light?

You can always let it float.

Or get Hygrophila difformis (water wisteria). It looks similar to water
sprite, but is easier to grow. And it does grow fast.

amazon swords (but need extra fertilization)
aponogeton ulvaceus (sp?)

These plants will probably be okay, but they get pretty large for a 12 gallon
tank. (Unless you get one of the new hybrid swords, that stay small. Look for
"rosette swords.")

crypto ciliata (read somewhere that it's the most hardy of crypts, and
not likely to melt with drastic environment changes. Which is likely
because I'm new and will probably do something dumb at some point.)

I have C. wendtii in my tanks. It doesn't need a lot of light, and it has
never melted on me, despite my frequent rearranging and transplanting.

african bolbitis
crypto balansae

Bolbitis will probably do well. C. balansae gets far too big for a 12 gallon
tank.

I would use 100% Seachem Flourite. It's the easiest. One bag would be enough.



Leigh

http://www.fortunecity.com/lavender/halloween/881/