Alberto, or Albright. Make sure you do 8 wraps either way and you will never have problems with slippage.

the J knot is great and one of the easiest knots to tie that I have found.

For 20 years my go to line to line knot has been the improved blood knot, makes a tapered end on each end of the knot and goes thru the guides both ways without resistance, Every reel I own has braid for mainline and the only thing that gets tied to it is a leader, either mono or fluoro, I have no doubts they work with all lines regardless of material or diameter. There are many good knots that are proven for joining lines, learn one and you will gain confidence and it will become second nature to you.

Double uni for me.....has been good to me.  Power Pro with Silver Thread or even light fireline with Silver Thread.  Have no troubles and quick to tie.  I do five wraps on the braid side and four on the fluro side.....awesome and easy.

Alberto and Albright are probably better knots, but I found the uni to uni easy to learn and I have used it several years without a problem.

So I finally had the opportunity to test out my Alberto leader knot, not on a fish though. I got snagged, DOH! Anyhow, 15# Super 8 Slick tied to Trilene 100% 15# Flourocarbon. It was a tighten the drag and hope the rod doesn't break ordeal. I was casting a wacky rigged worm. The leader knot held up great while the Palomar on the hook gave way. That was a 5 wrap Alberto too, tiny knot for how strong it is. I thought a little anecdotal "evidence" would be a nice addition to the thread.

ALBERTO !!! never breaks !!

The ones i use are the reverse albright and uni to uni. Recently i started using a new knot because of rods with micro guides and getting the leader through them, its called the sebile knot. All have worked great for me with great results.

Alberto knot, hands down. Uni to uni will do fine also. Just make sure you put on plenty of spit through the process. Cinch down tight and you are good to go. 

Casted into a tree this morning and hung up my lure.  10# braid with a 10# leader using an alberto and it broke off at the knot.  Line came back with a  smooth end not jagged indicating the knot broke not the line.  Wasn't in the least bit surprised, there is always a limit to any line and knot.

So I finally had the opportunity to test out my Alberto leader knot, not on a fish though. I got snagged, DOH! Anyhow, 15# Super 8 Slick tied to Trilene 100% 15# Flourocarbon. It was a tighten the drag and hope the rod doesn't break ordeal. I was casting a wacky rigged worm. The leader knot held up great while the Palomar on the hook gave way. That was a 5 wrap Alberto too, tiny knot for how strong it is. I thought a little anecdotal "evidence" would be a nice addition to the thread.

 

When your rod does break, keep the grip section.  When you hang up with your new rod, you can let out some slack and wrap it around your old grip a few times and pull free with that instead of busting your new rod.  Or you could just keep something similar handy now and save yourself a busted rod.    

the J knot is great and one of the easiest knots to tie that I have found.

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When your rod does break, keep the grip section.  When you hang up with your new rod, you can let out some slack and wrap it around your old grip a few times and pull free with that instead of busting your new rod.  Or you could just keep something similar handy now and save yourself a busted rod.    

That's exactly how I did it, I used the handle from my long needle nose pliers to wrap the line around and pull it free. It definitely would have resulted in a broken rod had I tried to use the rod instead.

I use an Alberto. No knot will be very strong if it's poorly tied. Practice, and test all your knots.

You won't ever break a rod if you take the right precautions.  Take all the tension off the rod by opening your bail or putting the reel into free spool, then wrap the line around a stick or around your shoulder and walk backwards.  Another method is wrap the line around the reel a couple of times, keep the rod perfectly straight and move the boat slowly with the engine, that's how we do it off a reef in 80 fow.