You can keep males of different strains in the same tent but you have to separate them before they start dropping pollen. It's not a good practice and if you do it you need to separate them before they start dropping any pollen. Once the pollen sacs are mostly formed the plants don't need a ton of light so if you have other rooms it's best to separate them early. You can use CFL's or even close to a window for outside light as you won't need a fancy light for the pollen sacs to open and release pollen once the plants are close.
I sometimes run multiple males of the same strain in the same tent and mix the pollen intentionally when I'm making seeds of landraces for the vault. But that's entirely different than males of different strains sharing the same tent if they're dropping pollen. I do it so I have seeds pollinated by different males so I maintain more diversity.
