How large would an 8 litre pots let a plant get?

Man if you top feed in a recirculating system using expanded clay,ring sprinklers and a tray, you could grow quite large plants in 8 litre pots because there roots ain't contained to the size of the pots, and your roots will grow down the channels of the tray like rope. If your hand watering or something like that i wouldn't grow very large plants ... maybe 30cm ... but man i wouldn't design your system around 8 litre pots that you might already have ... there pretty cheap n i would use 20 litre pots ... You can definately get 8 oz of 2 plants easy off a 400w hps ... And if you master your enviroment and use a decent strain like White Rhino or something you could get a full P .... well you want a gram per watt for an excellent yeild 400w/400g = just over 14 oz ... but you can do better and that will come with experience ...Man i might take some pics of my favourite system tommorrow with my digi and post em here .... cuz it might be too hard to explain cuz maybe we are in different countries and similar products have different names .... but top feeding in expanded clay using a tray to sit your pots in ... and the pots i prefer man are orchid pots sitting inside a larger pot .... its like half a pot sitting in a full pot ... and your roots hang in the bottom half, they form a 1/2 inch mat on the bottom of the pot, then grow down the channels of the tray towards the drain plug .... Do you have height restrictions or limited space ??... can you make a cupboard to whatever you want ?... i will put a daily check list on there for you too if ya want ... for ideal humidty, water temps, air temps,PH, E.C etc ... i've never posted pics on here before man so i hope its not hard to learn... should'nt be a problem