Great point @Clarke. I was wondering about this. My hope is that since the vent can be fully closed, any heat or AC blasting out should be highly minimized. My brother has kept a FW tank of his for years directly over this vent and never had an issue. Granted FW is much less finicky from my understanding vs SW, but I'm hoping keeping it closed will resolve any worries. I may invest in a cover/build a cover too that diverts all air in the other direction.