im kind of new to owning a fresh water tank. its been about five months since i got this fish and recently it doesnt look so good... he sits on the bottom a lot and the back half of his body is turning black. the turning black is a very new symptom probably in the past day or two. i changed the water about three weeks ago and just added some artificial plants. idont kno wat to do! i have a "broad spectrum fish medication"(not sure what its called but thats what the bottle says) it contains copper sulfate and for malin. i put the suggested amout in this morning.
please help!! thanks


