I would not even concern at 5-10 mns. I have a video of me draining my entire pico reef down to zero water for 33 mins, refilled and all was fine. 5-10 nbd, shorter the better.
imagine this power used on reef rock
let's say you got a tuft of bryopsis one day
you could spend 10 days identifying it with scope pics, then input some fluc and kill it, then get cyano or dinos for having killed it with fluc or you could lift out that rock one day, literally score off the bad part and put perx on the cleaned area and dispatch it, having never known it's ID or water parameters.
these steps combined with sandbed rinsing can beat any invasion in reefing. when you see a crudded up reef tank online, that's a reef mouth with no dentistry.