Hi thanks for letting me join ! I have a garden pond 12 by 24 by 2.5’ ive had it 7 years and never had much morts maybe 1 or 2 a month . A few issues with predictions. This summer we had very warm weather ! 84+ degrees in the pond i had allot ofmorts and 4 out of 5 koi die i had 175 goldfish and they were dying 1/2 a day i added water to keep it up due to evaporation 250 gal every few days ! The problem is the goldfish are still dying its winter now and my pond is filling with evestrough water and spilling over so its changing every few day i have filters and areation . But still im loosing 1/2 a day they look healthy just dead ?