Restores needs to many tapes

I have a problem with restores. We backups most of our servers with SLP to disc. After that it will be duplicated to tape (2 Libs). If I need a restore the job needs many tapes. Is there any adjustment to control the number of tapes? I think I can downsize the parameters in the Lifecycle_Parameter-file, but I´m afraid to get new problems. Has you take a hand in the tape-administration?