Need input for SOG setup .

So I've got my previous auto grow still going but I have already started vegging a mother plant for my next project . I've got a 2m x2.5 m grow tent with 2x400 w hps and I want to cover the whole space with clones and have the shortest vegging time possible (I'm going to make sure they root properly and then give them maybe 1 or 2 weeks in veg ) .
I'm thinking of using a coco and perlite mix for medium . The question is what size pots should I use . I was thinking 5 liters should do it . Any ideas ?

Or maybe as soon as the clones have rooted transplant them in 2l pots and flower them straight away ? I would need around 50 clones tho