I've been working on the same system, I've run a 1/2 inch feed line into each bucket with a 1/4 inch reducing barb spraying down into the bucket. It works very well, the problem is with the 3/4 return lines. I had 6 buckets hooked together draining back to the control res through one line, the control res would run dry. So I ripped it all apart to have another go at it. Now I've got 9 buckets with 3 return lines, 3 buckets per 3/4 inch return. I haven't tested it yet, I'm starting to think maybe I should have just run one return line for each bucket and stop screwing around. I'm using a 500gph pump and it's giving a good aeration effect with the water shooting into the bucket. Any input greatly appreciated. One other issue I'm trying to sort out is the airpump, I've tested a rena 400 with a 6 inch stone in one bucket and I'm not impressed ($50 pump). Is there a formula like 1 lpm of air per gallon or something? My buckets hold approx 30 gals, one big airpump would be great but it needs to be fairly quiet. I've spent every minute of my spare time trying to get this together for the last couple months. With lighting, venting etc. I'm starting to feel overwhelmed. Thanks for any help