To me it sounds like you are putting too much strain on your line when you are setting the hook. I'm not completely sure what you are doing but just to clarify... you do have it in free spool with the clicker on when the bait is out right? You should have your drag set already so when that shark takes the bait, you can click it into gear and you won't have to touch the star drag (unless you need to adjust it mid fight). A good way to get the right amount of drag is to tie the end of your line to a gallon of water, and lift it off of the ground, the drag should slide if you lift too quickly but if you hold it above the ground it should hold it. This method has worked well for me, hope it helps.
Ansel, I saw you at work today, so you already know I think thats a great idea 
FishinFool and ATKochno, I thought the same thing about the running hook set. Especially because that's when the break occurs. But when I upgraded to 80 lb. test and still had the same problem, I wasn't convinced it was too much strain on the line. But you may be right. I'll try and let the circle hook do its job and just start cranking next time.
FishinFool, we thought about the school hitting the line when it was under tension. After all, i do have bright yellow line on the reel. But it was happening to MrAnsel too and all his lines are clear. Even still, I'm not sure what I could do to remedy this, maybe use blue or camouflage colored line? 
ATKochno, We mostly fish on the east coast where there is high surf, we can't really leave the bait in the water with just the clicker holding line tension. The waves would strip line off the reel. But I do like that gallon of water idea. Seems like a good benchmark on how to set the drag for a fight.
Thanks again, guys.
I fish boca grande area hit me up when ur down here will hit the sand
Just got back from the tackle shop and thought I'd share my plan. Here's what I'm going to do with my two 9/0 reels:
*Leaving the 80 lb. test yellow mono line on this one. I bought some aluminum crimps and will use them in place of a knot. Additionally, I will tie an overhand knot on the tag end in case the line slips through the crimp (thanks for the tip, JPSHARK38). This will address my concerns of knot failure and I can compare the action to the other reel.
*Putting 80 lb. black dacron on the second reel. The dacron holds a knot better than mono and can still handle some abrasion (more than braid can, but not as much as mono). Also I like the idea of no stretch and feeling the fight. FishinFool91, you said fish can attack the line so I got black color to make it much less visible.
*No more running back to set the hook.
*Going to a new location to try to avoid underwater objects, but will eventually return to the same spot where the line breaks happened.
Any concerns about this approach? Let me know, I'm interested.
I don't know when I'm fishing next, but I'll fill you all in. Thank you all for the advice, I'll let you know how it turns out.
Good luck! Tight lines!
Just got back from the tackle shop and thought I'd share my plan. Here's what I'm going to do with my two 9/0 reels:
*Leaving the 80 lb. test yellow mono line on this one. I bought some aluminum crimps and will use them in place of a knot. Additionally, I will tie an overhand knot on the tag end in case the line slips through the crimp (thanks for the tip, JPSHARK38). This will address my concerns of knot failure and I can compare the action to the other reel.
*Putting 80 lb. black dacron on the second reel. The dacron holds a knot better than mono and can still handle some abrasion (more than braid can, but not as much as mono). Also I like the idea of no stretch and feeling the fight. FishinFool91, you said fish can attack the line so I got black color to make it much less visible.
*No more running back to set the hook.
*Going to a new location to try to avoid underwater objects, but will eventually return to the same spot where the line breaks happened.
I don't know when I'm fishing next, but I'll fill you all in. Thank you all for the advice, I'll let you know how it turns out.
Sounds like a good plan and should work out.
The great thing about fishermen, we are never ok with a defeat of any kind, we have to always improve.
New problem. I'll post a new topic...
New problem. I'll post a new topic...
Haha 
Dude, if you guys busted off 11 one trip or a bunch per trip then it sounds like you guys mainline is running across another Tippers back or theyre spooking and running into your lines while its stretched tight and popping it. It happens to me while Tarpon fishing and their backs are far less abrasive than a sharks back. On AMI Ive actually watched the line break on another fishes back when we get hit close to the boat as the pod is passing in close. Dacron is pretty hardcore and should help if this is in fact your problem, or upping your mono mainline but then your losing yardage. You can also go with a crazy long tailwhip section, like 30ft of 400lb but that just starts to get awkward to work with. Some guys always do it though.
Nice! Thanks Sandrayusmc for the confidence. The girlfriend got me a new spool of dacron, so we'll see what happens. BTW, sorry to hear about your canoe. 
I'd be pissed!
Just got back from the tackle shop and thought I'd share my plan. Here's what I'm going to do with my two 9/0 reels:
*Leaving the 80 lb. test yellow mono line on this one. I bought some aluminum crimps and will use them in place of a knot. Additionally, I will tie an overhand knot on the tag end in case the line slips through the crimp (thanks for the tip, JPSHARK38). This will address my concerns of knot failure and I can compare the action to the other reel.
*Putting 80 lb. black dacron on the second reel. The dacron holds a knot better than mono and can still handle some abrasion (more than braid can, but not as much as mono). Also I like the idea of no stretch and feeling the fight. FishinFool91, you said fish can attack the line so I got black color to make it much less visible.
*No more running back to set the hook.
*Going to a new location to try to avoid underwater objects, but will eventually return to the same spot where the line breaks happened.
I don't know when I'm fishing next, but I'll fill you all in. Thank you all for the advice, I'll let you know how it turns out.
UPDATE
I know I'm bringing up an old post, but some of you guys were very interested in the results of what I'm doing here. I wanted to share that I haven't strayed from this approach in the past 4 months and have generated some fantastic notes. I want to keep fishing with these 2 setups until the winter months and make my conclusions from there. I figure a year of working an experiment makes for pretty strong results.
I attach my top shot with barrel swivels to prevent the knot slippage. Watch how your lead is positioned on your rigs, it can make a difference in how it reacts to its surroundings. AKA rocks and such with the right current can chafe the line without noticeable movement on your part. I use a T rig for surf:
Basically its a two pyramid weight on both sides and the center rig is about 3 ft down with the bait attached, the idea is to steady your main line with two opposing leads ( preventing swaying of the main line ) the center free to catch current and get off the bottom. Hope it helps! Tight lines always!
check your guides in your rod with a magnifing glass and your finger if you have ceramic insets on your guides and one of them is chipped it will cut through any pound line like a razor blade also check if you have metal guides there could be a defect in one of your guides like a burr or small crack or a flake of crome missing this will cut your line real quick check the sides of the rollers if you have any not the roller it self but the housing around it if the guides are not straight the line will rub on the side of the roller and break do the same with the tip real up your top shot /wind on as far to the leader as you can then have a friend pull it out under pressure and feel and watch carefully to make sure none of your tag ends are getting caught even if they get caught for a split second thats enough to undo a knot
All are great advice and I am glad for the great response to this problem we are having. From what I have been reading I am leaning to it being cut off by the other sharks during the black tip migration, coral rocks in the water or perhaps both. As of late we have had almost no break offs but don't know if because of changing out the lines or fewer sharks this time of the year. Went from having 11 runs a night to having 2 runs a night. We should know more when the next Black tip migration starts. Again thanks for all the great advice.
How does the end of the line look when you get it in? Black tips and other small sharks run in to your line with their mouths open and cut you off. When i fish in Boca grande on the west coast i never had that problem but when we visit the Stuart or Miami area we noticed this would happen multiple times each night. First you would get a run straight from hell and your first thought would be that you have a monster but shortly after it stops and you reel in a stub at the end of your line. One time on a beach in Stuart we actually caught a 4 foot black tip midway on our line (200lb bull-buster on a 16/0). He got tangled in it so bad about 100 yards away from the hook.
The way we originally tested the theory of a fish swimming into your line was we kayaked a bait with a rock tied to the hook and a big float on the swivel that reached the surface. when we got the run and got cut off we kayaked out and brought back our rig and the bait was untouched. i would say 80% of the time the cut would be made no further that 100 yds from the beach. (Depending on our rigs and time of year we use this as a safety measure to get equipment back)
keep in mind the time of year and your location. Whatever it is overcome it and KEEP FISHING!