I just recently added a 72 inch by 28 inch rocky background from the big retailer Universal rocks, and 2 days later my 18 inch, 3 year old peacock bass is dead, along with my 5 year old synodonitis eruptus catfish, and my last 3 fish remaining are gasping for air! My tanks filtration is still running the same, no less since I added the background, also before I added the background I washed it as advised from universal rocks. Any suggestions as to what may have happened and what do you think I should do to save the remainder of my fish?