95... If you are DIY at all, you will soon collect an entire toolbox full of reef tools and you will have to yell at your spouse to not use them on the car or other non reef friendly applications.
KarlBob's Corrollary to #95
You will soon collect an entire box full of tools that belong in other parts of the house, and your spouse will have to yell at you to not use things from the kitchen (or other non-reef areas) on the reef tank, and to put things back where you found them.