I need help identifying a plant in my aquarium. I obtained the plant by accident when purchasing others.

It was quite small when I planted it, anyway, it grew and grew and grew. Next thing it started regenerating itself by growing smaller versions of itself on its leaves.

What it then does, is these smaller versions grow roots on the plant and then when they are big enough, break off and float to the surface unless they are planted.

I've never been successful growing live plants, but this plant just can't be killed off. I now have 5 large versions of it in the tank and and some of the leaves literally grow overnight. It is quite amazing and while I am quite impressed with them, I just want to make sure this is not something that is a pest or weed and dangerous to my fish. So far it doesn't seem to be, as my livebearers love eating the algae of them and also biting off the smaller versions as they grow.

Can anyone help me identify this plant for me?

Can you provide pictures?

java fern?

judging by what you are saying about the plantlets growing on the leaves its gotta be java fern or amazon sword, google those 2 names and see which one is the closest.

These are the plants in question

Indian fern - Broad-Leaf Water Sprite (Ceratopteris cornuta). I should know I have it. That is a great plant from removing excess nutrients. As you know all ready it can grow floating or rooted to the substrate.

Awesome! Thanks Ted for helping me out. It's a great plant and I'm happy now I know it's OK to have.