Bob,
The questions I have are:
1. What is your CURRENT goal for this pond?
2. Did you add the bass only to get rid of the goldfish, or is the current goal to raise bass?
3. Why did you want to get rid of goldfish anyway?
4. Are you out of keeping trout for Good?
The largemouth bass will eat the goldfish, no doubt about it. But, I'm guessing that eventually the bass will eat all of the goldfish as they are not a speedy fish. In the mean time the bass will be reproducing and eventually you will end up with a lot of stunted bass in your pond. So, if you want to have a healthy bass over the long term you need to think about a forage fish. Are Bluegill bream available in your area? Since you've already added 10 10in bass, consider adult bluegills.
I am guessing your basin is in a Pine/Spruce Forest? It may be acidic from the needles and that's why it's black.
