i used peat plugs in my GenHydro WaterFarm and they worked awesome! they were these weird 2 1/2" - 4" long plugs plrobably 1/2" square at the top where the seed went and tapered down to the bottom. anyhow.. they did AWESOME! WaterFarm used a drip ring up top (pushed by air displacement) and i added air stone to the res for the roots. worked great. peat/jiffy work AWESOME in hydro systems. hell, GenHydro SELLS Rapid Rooters from their website!!! clearly, THEY endorse them... (fyi this wasnt a GH endorsement lol)
to each their own, just know tom is right. i understand you have a personal preference. but to say that peat ("dirt"? WAY off) would not work in a hydro system, is false!

Shack