Could anyone please tell me what the best way to remove plants from an NFT system would be. There are some from cuts and some from seed growing within the same tray. The roots have all established but I know at least a couple will be male. Should I crop the plant at it's base and then feed with enzymes till finish or try and approximate it's roots and remove completely?

Chop at the base of the stem, I assume you have em in rockwool? Leave the cube in the tank and cover the hole where the cubes are with some B&W and Bobs yer auntie Ya don't wanna be messing with em roots

You could also use some cannazym, it helps to break down the dead roots into useable nutrients.