My Eheim pro 3 is leaking and even after a good clean an re-grease I haven’t been able to stop it so I’ve ordered a replacement. But I was wondering if there was a way of rejuvenating old seals so that they can be used again? I know you can soften brittle rubber by boiling it, has anybody ever tried it with a rubber seal? At £10 a pop it would be good if they can be used again!