AHA!! Finally, the aquatic plants forum gets it's first posting..

OK, where do I begin....
Firstly, u need to do a little bit more reading up about planting a tank b4 embarking on it. Keeping fish is easy, keeping plants that thrive in an aquarium (those lush green aquariums u see in books) is another thing.

For starters, u have perfect equiptment for keeping fish (bio-wheel filtration), but absolutely lousy equiptment for plants. U see, the requirements for fish to thrive and plants to thrive are quite different (Actually quite the opposite). Fish need an abundance of oxygen, plants need an abundance of CO2. To grow plants properly, u need to artificially inject CO2 into the tank. And because you spend substantial ammounts of trouble dissolving the CO2 into the water, u want minimal surface turbulance/aggitation which would release the CO2 you put in. Bio-wheels are a big NO-NO in a planted tank. Keep the surface as still as possible.... no bubble wands or anything like that. Add CO2 and the plants will produce the O2.

I suggest you check out these 2 DIY links to get you started cheaply with a planted tank...
http://www.qsl.net/w2wdx/aquaria/diyco2.html
http://www.nfis.com/~hartland/aqua/co2.htm

Next, Lighting: the recommendation for planted tanks is an average of 2W per gallon.... With your 2 light fixtures in a 125gal, u're WAY short. At your ligthing level, only Java moss would survive... barely. I would suggest you add another 2light fixtures and then, u could possibly grow the lower light plants like Java Fern, Anubias, Crypts, Bolbitus and possibly Hygrophilia Polysperma.

Just a lot to learn about planting aquatic plants b4 jumping right in... gotta add the right substrate, learn about fertilisation of cleated metals, adding Co2, substrate heating, ligting spectrum....... wow... I could write the whole night long.

Anyways... I just started learning and planting aquariums about 6months ago... so still learning as well. Absolutely fabulous to have an aquatic garden in the living room...