scorpion or spiders can they live off minnow fish?

A spider won't eat fish. I scorpion might nibble on one but it will really stink pretty quick. How about trying waxworms, or small crickets, or bee moths, or maaaaybe mealworms.

There are some spiders that may eat small fish as long as they are alive and moving, same for scorpions.

Not all arachnids will feed on fish though, and may just ignore or fear fish.

This is something you can experiment with, but un eaten food should be removed from the cage.

Given feed insects are easy to raise, you might consider breeding your own feeders, such as crickets, meal worm, or even fruit flies for spiderlings.