so I am thinking that I should treat them as sativa until they show strong characteristics either way? Light on nutes 

how about acidity? do they prefer a more acidic or basic feed? i.e. would the plants prefer it 6.3 rather than say 5.8. I have never been sure on this and often mix it up but a long time ago I read it prefers different pH levels dependent on the stage of growth.

Some are more sensitive to this, others could care less - just Feed me Seymore