Another boat question

The garden hose in your pic, is that a type of flush? Mine has attachment but ive never used it.
Yes, I found an attachment that screwed right into that inlet and I pump water directly into the motor. It falls down through the lower unit and the tell-tale. It doesn’t work well on our low water pressure here so I started using the tub as backup. We got an auxiliary pump recently and it can force the outboard to pee without the impeller running at all but I still like having water down there too.

flushing salt or just running it a few times per winter.