BuddyPress.org

You need to figure out what is causing the white screen.

Turn on WP_DEBUG and view the notices that are logged or displayed:
https://codex.wordpress.org/Debugging_in_WordPress#WP_DEBUG

List the notices here if you want us to attempt to diagnose your problem.

My first guess is your problem is memory-related as your webhost might have restricted memory usage. Or if you’re using a caching plugin that is not correctly configured.