My pond was accidentally overdosed with about 8x the amount of the D-Solv pond cleaner. The next morning the fish were noticeably lethargic and clearly oxygen deprived. Due to work restrictions I wasn't able to get home for about 27hrs after the fact. I have just done a 50% water change and added a few more temporary small air pumps until I can buy a bigger pump tomorrow.... A few of the small fish have died but the large fish seem relatively ok. I just walked back inside from my water change and wondering if anyone knows anything else I should do?