i want to run about 60 plants as im in the loft and not a lot of headroomi had built a 36 plant nft using 6 5ft pieces of 4inch pvc ,90's and t's. it worked very well and tubes wer full of roots by the end of each run.. i actually had roots cause cloggs were the nutes couldnt make it back to the rez and over flow a few times.. i have now switched back to flood n drain..