Pea Gravel Question(Its Turned black!)
i have Pea Gravel, Just natural stone nothing fancy in my 55g, the numbers are good, but the Gravel has turned black, any ideas on what would cause this? there are 2 Hydors in the tank, a number 1 and a number 2 plus the flow from 2 HOB filters and a canister filter and the Flow from the in tank UV sterilizer so im pretty sure i have flow covered. i just have no clue why the rocks are turning black.
It is the landscaping Pea Gravel from wal mart, it was white,light gray and brown to start now everything under the top layer is Coal Black, im not so sure this is good for my fish or plants anyone have any ideas at all?