plant suggestions for a 29 gallon guppy tank

I have a 29 gallon tank that I am going to attempt to breed guppies in.
I already have the tank set up, and it has a few danio's living
happily in it, swimming around the plants I already have...

I am looking for 3 different questions to be answered...

1. What makes a good "ground cover" plant in a guppy tank? I would
prefer to have a covering of some plant better than the gravel.

2. What is a good bottom plant to allow the fry to hide?

3. What is a good top plant to allow the fry to hide? I don't want a
"loose bunch" of anacharis floating around - I want a good looking
tank, and I feel that that would detract.

Tony