So this sand will kick start my.cycle a little bit before i add the live rock? And then the die off from lr i order will do the rest of the cycle?

Yep, no rinsing required.

Okay so! No washing sand. Ad water. Then salt. Turn power head on n let it mix... Then turn power heads off and add sand? Correcto? Everyone agree this is good? Hahah havent even got my first sw tank setup yet and already confused beyon beleif bahah

Correct, I would have a heater in there too, temperature changes the salinity readings.

Yeah heater to lol what temp.shoulf i be lookin at for cycleing? I always max out my heaters in fw tanks to cycle

You got er:)

You'll be fine relax all in all if this step gets messed up there's no bad effects to be had just a little extra work:)

I like to keep my tanks around 77-78 degrees.

78-80 is fine

Thanks! Haha everythings sooooo different the fw. Im assumeing once its all up and goin itll get easier haha if this goes well, when i upgrade my arowana to a 10 foot tank, my 240gallom fw tank will be converted to sw to

Make sure your old tanks have never had copper in them , marine inverts cannot handle the same amounts of copper as freshwater even just the silicone can cause issues.