right now i am spooled with 12lb mono backing, 20lb braid and 12lb floro leader that is 6ft long.... should i use a mono or floro leader?

You can vary your leader type to match up with your presentation. If you are fishing a top water bait you would probably want to use mono (flouro sinks and can adversely affect the action of some top water baits). Conversely if you are fishing a light weight presentation that you want to keep close to the bottom flouro might be a better choice.

by the way, if you are fishing a heavy jig, big crankbait, spinnerbait or any other presentation that will overpower the floating or sinking characteristics of your leader material then it really does not matter which leader you use (I would tend to favor monofilament there as the knot strength is generally stronger)

In general you can use mono or floro leader for all techniques. 

Having said I generally have mono leaders for treble hook baits and top water.  I use flouro for bottom contact techniques. 

What techniques will you be using this set-up for?

45 minutes ago, BiteFiend said:

What techniques will you be using this set-up for?

depends, i can change or i can use floro... it is for mainly in general

2 minutes ago, AustinHellickson said:

depends, i can change or i can use floro... it is for mainly in general

If it were me, anything on top of the water would get mono leader. Anything below the water; fluoro. Anything in grass; straight braid. 

I would go with a Fluoro leader, no matter the application.

1 minute ago, thebillsman said:

I would go with a Fluoro leader, no matter the application.

Just curious, why?

Well if it's going to be attached to braid, its most likely going to be an application that doesn't lend itself to line stretch; ie. getting a good hook set with jigs and soft plastic presentations. Also, while fluoro isn't as stretch-proof as braid the right brand can have much less stretch than your common mono options. And last, fluoro is just a little less visible underwater which is always a bonus.

Make sure you use the proper knot bringing mono to braid and braid to fluoro together. Try out a few options and see what works for you! 

27 minutes ago, thebillsman said:

Well if it's going to be attached to braid, its most likely going to be an application that doesn't lend itself to line stretch; ie. getting a good hook set with jigs and soft plastic presentations. Also, while fluoro isn't as stretch-proof as braid the right brand can have much less stretch than your common mono options. And last, fluoro is just a little less visible underwater which is always a bonus.

Make sure you use the proper knot bringing mono to braid and braid to fluoro together. Try out a few options and see what works for you! 

I am using a double uni knot... works fine right now... thanks for the help.