[demosthenes]

1. No. You can not just clip the leaves and replant them, there needs to be a rhizome for the plant to continue growing.

2. Damaged leaves do not repair themselves. But they also never really rot. (other plants do, java ferns are just really hardy. and they do rot eventually, just realllly slowly.) So only clip leaves off if they are unsightly or bug you for whatever reason.

3. Lights are far more important to plants that nutrients. If you want to grow nice plants, get a nice light. Once you have good plants, than you can make them look better and grow faster with extra ferts and CO2. But you only need those if you have faster growing plants. That being said, Flourish Excel adds carbon to the water and stops algae growth, so that may do you some good. Excel will do more to kill algae than it will to help java ferns grow though, so it won't really work wonders, but its worth a try.

Also, when you take pictures of plants, add in a quarter or a penny or something next to them so we know generally what size they are, otherwise it can be hard to tell.