I'm getting a free 55 gallon tank stand and accessories from a friend who cant take care of it anymore. He hasnt changed the water in a long time and all but one fish has died. The surviving fish looks really bad it has holes in its head and a silver line going down the sides of its body. There is a lot of driftwood in the tank, most of it came from the store but a few pieces came from his back yard. I'm going to clean the tank with bleach but how do i clean the driftwood, or should I toss it and buy new stuff? Is the fish curable or should i kill him?