Floating Plants
Good morning gaby...
I have several large tanks of Fancy Guppies and I like to float Water sprite in my tanks. Water sprite is an interesting plant, it only thrives in extremely clean water conditions. If the Sprite doesn't grow well it's usually an indication your tank water isn't clean. I've used it for years in my tanks and it works great for hiding Guppy fry.
If you want to get a little creative you can attach Java fern and Singapore moss to floating pieces of driftwood. I've found ferns and mosses grow faster in low light conditions if you can get the plants closer to the light source. The fern leaves get longer and wider and the moss gets very full. Perfect for hiding the little guys too.
The lighting in my tanks is less than a watt per gallon of tank size. I use one bulb per tank, T8s or T12s and 32 to 40 watts. My plants do best with 6500 K bulbs, these best mimic natural daylight.
Don't forget to maintain good amounts of macro and micro plant nutrients and do regular and large water changes. These two areas are very important if you want a well planted tank.
You'll need to keep an eye on your other plants. You'll change the lighting conditions by floating some plants and reduce the amount of light getting to the bottom of the tank. Your existing plants may not do as well. Time will tell.
B