I HAVE A 55 GALLON TANK WITH 2 OSCARS, A JACK DEMPSEY AND A PIKE. THEY ARE ALL ABOUT 4-5 INCHES. FOR THE PAST COUPLE OF DAYS THE OSCARS HAVE BEEN VERY INACTIVE AND THE PIKE HAS WHITE SPOTS ALL OVER HIM, KINDA LOOKS LIKE ICH BUT THE SPOTS ARE NOT ON ANY FISH. I HAD A PLECO THAT DIED LAST WEEK. DOES ANYONE KNOW WHAT COULD BE WRONG WITH MY TANK? THANKS