Durban Poison Browning leaves

plants are at 4 weeks flower
Just notices today the top leaves are getting a brown colour on them. Just curious if it is strain related. Currently not on all of them

Thanks

Sorry I haven't run a Durban Poison yet but based on the pic I would say that you have too much of something like light, heat, nutes, water or something. I say that because I see some leaves that seem to curl upward which indicates to me that the plant is trying to dump as much water as it can to stabilize itself. Tell us more about what you've done up to this point: what kind of light you are using, how close is it to the canopy, how often do you feed/water it and with what and how much, etc.. Maybe someone can give you some better answers with more info.