99% of the time, well water is great for fish. Here's where you should be cautious. Each well is drilled for a specific purpose, and designed to deliver a given range of flow. If your well isn't large enough or wasn't finished to create a higher volume, a bigger pump won't help. Consult with a well driller in your neck of the woods and pose those questions.
To be confident of water quality, have it analyzed by a competent lab to find out what's in it. Then, you'll know for sure.

Teach a man to grow fish...
He can teach to catch fish...