2000 Honda S2000 Clutch is acting wierd

My clutch started slipping about a month ago and it was to the point where I couldn't even baby the gas past 4000 RPMs with out it revving up pretty substantially.I was about to buy a new clutch and flywheel when I noticed that the clutch fluid was really low. I was under the assumption that the clutch slipping and the clutch fluid were completely irrelated but for the sake of experiment I filled the clutch fluid up to the max and took the car out for a drive and noticed that the clutch was almost back to its old self. I was running all the way up V-Tech and beyond (7000-8000 RPMs) in first gear and having limited slipping only in the higher gears. I was thinking that if adding clutch fluid helped solve the problem, then bleeding the system or checking for leaks in the slave cylinder would fix the problem. Any recommendations or thoughts at this point would be a world of help! Thanks.