Not sure if i can ask clarification using answer feature in here, but… @Marcel, it’s not clear what “wordpress just don’t see it” means a) Avada’s Server Environment page shows a PHP Memory Limit or b) a lower WordPress Memory limit?
I am guessing is b). In this case, have you edited wp-config.php and increased memory limit. e.g define( 'WP_MEMORY_LIMIT', '64M' );
Anyway, if your theme or plugins are consuming 256M memory and it is not a complex app or website, maybe you should considerate “leaner” themes and plugins and/or dedicated and managed WordPress services like Dreampress by Dreamhost or WPEngine.