just my two cent
did you activate or "proof" the yeast before hand?
The water should be lukewarm. Yeast activates best in water that is between 90 and 110 degrees, before you dumped it into the sugar/water mix?
if your not getting C02 after 17 hrs i think you'll have to start over.
in fact you should get a reaction within one hr. i did DIY CO2 before going to a pressurized system.
after i'd finish the mix, i'd place the bottles on a heating pad set at low for 20 mins and get a nice kick start. not to long mind you, you don't want to over heat the mix.
airstones worked fine for me, plenty of pressure will build up to push out that line!
in fact you may think about putting a Y with a small valve you can open to vent into the atmosphereat lights out, if the bottle over pressures,from say a cloged line it will burst and you'll have a big mess to clean up
or do what i did, and that was to Y into an empty bottle (large) bottle at night and after two or three days. a good amount of pressure builds up in that empty bottle, then you can recover it back into your tank without wasting any CO2
good luck, let us know how it works out