Tapes and recycle

[Nazir]

I have been working with TSM to make backups of my servers.
The TSM server is in Windows NT. It works with tapes too.
The TSM makes backups and keep it in hard disk, after this sends the data to
tapes.
TSM uses the tape to write the backup and after this needs more tapes. But
the old data stays at the first tape.
What Can I do to reuse or recyucle the tapes?
I don4t want to lose any data from my backups.