When is it Time to Apologise to a Fish?

I am sorry my piscatorial friends because I have failed you! We have a 1,300 litre fish tank in the front garden and although it is the rainy season, the water was at about half the level it could be. Last night I decided to top up the tank a little to get some fresh, oxygenated water in there. I forgot I had done that and left the water running. At 2 am the mother in law, who lives next door, heard our water pump going on and on and got out of bed and stopped the water. In the meantime at least two fish died: probably because of the cold. One or two went over the overflow as is their wont when the tank is full. So it is time to apologise to those fish that didn't make it through my inadequacy. I don't know how we wandered around the garden last night, as we did, how we didn't hear the pump because it is just outside our bedroom ... So, really sorry for that! DW