Beginner plants?

I've been thinking about asking here for some recommendations of one or two beginner plants. I don't really want to do a "planted" aquarium; but I'd like to maybe add a real plant or two to accent or accompany my plastic and silk plants, for looks and to help a little bit to improve water quality. I'd like to maybe start with just one kind, that I could put a couple of here or there, that will add to my décor without overtaking everything.

I'd like something relatively easy, low maintenance, no fertilizer requirements, for my freshwater community tank/s. One is 75 gallon, and one is 20 gallon. Both have undergravel filters with gravel as the substrate. I have regular (not grow-lights) lights that I keep on about 8 hours a day with timers. Fish (in case it's a consideration) are angelfish, one Pearl gourami, Glo-light tetras, Black Neon tetras, and assorted cory cats.

From what I've read and seen pictures of, I'm thinking about either water sprite or Java moss?

I read I could attach the Java moss to larger rocks or wood. Some reviews say it minds well... and others say it's hard to keep in check. I'm willing to do trimming or thinning, but would this stuff take over my aquarium? I'm thinking if I didn't neglect it (or maybe if I did), it won't run rampant... true? How often do you have to prune or thin to keep it in check?

I also like the looks of water sprite. Would this plant fit the bill for me? Can you attach it to things like the Java moss? I'd rather have something I could pick up and move around (with or on décor) that isn't rooted in the gravel substrate (that I'd have to vacuum around).

Do you all have any recommendations or caveats for someone who's never had real aquarium plants before?

Java moss, java fern, and anubias,are what I recommend for newbies. They can take the low light most people have and they grow slowly. All of them can be attached to driftwood with cotton thread until they eventually attach on their own. Now I know of some people who for some reason or another can't seem to get those to grow. It's unusual But if that's the case you just have to try with an assortment of plants till you find one that likes your tank. I would recommend staying away from certain "chain" petstores. They sell non aquatic plants like dracanea and other houseplants which will eventually rot under water. After you get your plants I would recommend a 10-12 hour light cycle for better growth.

I want to start up my first planted tank. I want to use a 20g long for this. I need suggestions on what substrates, easy to grow plants, hours of lighting, and so on. Eventually, I will want to breed guppies in it once it is fully established. All opinions are welcome. Thanks.

Two watts per gallon is the usual rule that will grow most plants. For a 20 long, a florescent strip light is sufficient to grow low light and easy plants like Anubias, java fern, java moss, water sprite and sword plants. Leave the light on for about 10 hours a day. Using just plain gravel is fine. You can add liquid fertilizers or tabs special made for planted tanks but it's not needed for slow growing plants like Anubias, and java fern.  

I seem to always have some water sprite for free if you want some. Can bring it to a meeting for you but let me know ahead of time because I get rid the extra about every 10 days to two weeks. I use it with all my guppies. I plant it and it will usually grow out the top so I have to trim it. It can cover the water surface and inhibit oxygen-carbon dioxide transfer at the surface.
Also, my experience has been that all plants don't necessarily do well in every water so try them all out-- especially the free ones! Maybe you'll be lucky and have some of that good for most plants kind of water. Good luck.

Thanks, guys. If either of you need to thin out your plants, I'll gladly buy some from you.

You'll have to hit me up this week. I'm thinning out then going to Indy for the Goldfish show this weekend.

Gina, I can swing by tonight if you guys are going to be around. If not, next week works too. Just let me know.
Thanks

I'll be home at 7pm if you want to stop by.  

Keep in mind the 2 watts per gallon is a rule of thumb. It isn't a hard set rule. There are a couple of factors that could affect this rule. First, water attenuation. The deeper the water the more light will be diffused away from its target, the plant. Conversely a relatively shallow tank like the 20 long you mentioned would require less light. Dirty water would also filter more of the light from the plants. Second, fixture efficiency. I wish the rule was based on lumen output instead of power input, because two lamps of the same wattage will have very different light output. For instance a 60 watt incandescent uses a lot more energy than a 13 watt compact fluorescent but they output the same amount of light. This is because the incandescent is inefficient at converting power into light and instead loses much of its energy to heat. Similarly an LED fixture would be even more efficient. Additionally the reflector shape has a significant impact on the amount of light that escapes the fixture. A parabolic reflector is best. Third, light temperature. Plants like light in a certain spectrum. This spectrum varies on the plant, but most of the easy stuff prefers light under 3000K (reddish) or over 6000K (bluish). If you are providing light outside the desired spectrum that is energy that the plants are not able to effectively utilize and is thus wasted. Finally, the plants. Plants like different levels of light. Java fern can stay alive on almost nothing. For a while I was growing it in a 55 with two T-8 fluorescents, no ferts or carbon. If I tried to grow something more light intensive it would wilt and die. Typically the red plants like lots of light.