My aqurium is cycled, but it seems like 1 fish died everyday. 0ppm ammonia 0ppm nitrite 80ppm nitrate I know my nitrates are really high, but in am on well water and it's naturally 40ppm coming out. My PH out of the well is 7.6 but my aquarium water is 8.8. Even when I do a water change it goes back to 8.8. Could the nitrates or oh be killing them? Please help.