how goes it?
i too used nft for a few grows and had good results. i made it out of pvc pipe.
i used 2 inch pvc for clones, and starting small plants, and then put them into 6 inch pvc. the only problem i had was that the root mass on the adult plants would sometimes block or slow down the nute flow in the 6 inch pvc, so you need to put an overflow in each tube.
i ran the pump 30 minutes every hour, sometimes i would run it 24/7.
the 24/7 worked well, but keep an eye on roots clogging the drain holes.
as long as the tubes are on a slight angle towards drain holes, 5 degrees at least, you should be ok.
you are correct on the nutes, same as bubblers. actually your res. would be set up similar to a bubbler except there would be a pump to push the solution through the tubes. i am sure you`ll be succesful in the nft.
if ya got anymore questions, drop me a line and i`ll try and answer them for you.
good luck
peace
and
grass