H2O What should I look for?

This might be posted somewhere but I didn't find it. I want to make better beer so I am going to have my water tested. (my last two batchs had a funny after taste, a little bitter.). I am on a well and all I know right now is that the hardness is 8.2 . I do use a water softner. My water taste great but I know that does not mean it is great for beer. What exactly should I have them test for? As I go through these threads and read I am a bit overwhelmed by the amount of information. What exactly do I need. Thank you.

By the way I bypass the water softner when I do All grain but don't when I brew extract. Thanks again

Just get the Ward Labs test for $25. They do a good job and test for everything of interest to a brewer under normal conditions. If you know you have abnormal levels of strontium of manganese or something like that you would have to order a special test but that is unlikely.

With respect to the bitterness - look at the sulfate. It intensifies the impression of bitterness from hops and coarsens it. Where fine bitterness is required, sulfate should be minimized.

Generally speaking 50 mg/L or more of calcium (except in soft water beers) is considered good usually supplied from the chloride (as it mellows flavors) as opposed to the sulfate (which accentuates hops) though you may want some of this character in your beers. See the Water Primer in the sticky at the head of Brew Science.

Bypassing the water softener is a good move.