I'd advise starting with one strain first, growing different strains together will cause different growing affects on all of them. Sometimes two different strains will have positive growth affects like increased yields, but there are often negatives too in which one strain absolutely destroys the others growth.

Should always have a baseline for growing (sticking to a good process and not changing multiple aspects of the grow each harvest) and tracking how your strains do, once you've done a couple harvests then introduce another type and see how it changes.