Be careful what you throw away in your tank that is floating at its surface. This stuff is often discovered as a stole away floating in your tank. I almost threw away mine because I thought it was the beginnings of duckweed. The difference in color you see to the right is the difference of bulbs being used the yellowish color is produced by 6500-6700 bulbs.
this plant is a natural floater and comes 3x the size naturally than it does for aquarium use. Its also easily established in waterways so be careful to put your waste in the trash and not down the toilet/drain.
stay away from this plant, once you have it its hard to get rid of it. grows like a weed, waste of nutrients and co2 on this plant, because when your other plants could be benefited from the co2 and nutrients.
It seems some people don't like this plant and claim it's hard to get rid of once you have it, I haven't tried to get rid of it yet. My shrimp love it floating and spend most of their time under the twirling mass of Riccia and what I have attached to a rock is so bright green it's hard to get a photo between the color and the bubbles reflecting light. I love it's strange structute and the leaves are called antlers, I find it easy to trim and the cuttings just float to the surface and start a new pod for shrimp to play in or it can be removed with a breeders net. It is a very easy plant to grow and a very hard plant to kill, I haven't done any test on how long it can survive out of water but I have tossed it in the trash and it's fine after a several days and could be put back in the tank so be careful in disposing of this plant.
This is one of my favourite plants... I tie it to upturned seashells and it grows upwards in little bright-green clouds. The colour is amazing. My shrimp like it alot and it makes great cover for fry, if you leave it floating. I've got it in two tanks--one with lots of light (the shrimp tank) and a low-light tank where I let it float. Both do really well.
I believe this plant requires a lot of light. In my tank it grows but does not thrive, and I assume I have low light. At the bottom of my tank the riccia melted away, but grows at the surface or on a root which is quite high.