Why does "IT" always happen at night

[Drock169]

for the ich thing, thats just part of its life cycle, it usually drops off the fish during the day and reattaches at night

[Ken]

Hi, sorry to hear of losses, but this questionit is something that is not new to every hobbyist, I'm sure it happens to many hobbyist, just before we turn in for the night, one last look in the aquarium in hopes for better things in the morning when we wake up that the fish fairy will be here to save the day, but in this case the night. Many things can happen between day and night and how the dynamics of the aquarium is functioning and its inhabitant. I not saying this is the case for your aquarium but your question does raise many valid points on why things happen when we are away on holiday or asleep at night or not at home, why the main pump decides to die today and not yetesday when we're at home etc...... When fish are already weak, at night when nocturnal inhabitant comes out to prey or in search of food, this is oportunity to take advantage of weaker sicker fish. At night when the lights are off, we have a low pH due to co2, less o2 level, sick fish ends up near suction line of powerheads etc. These raises more stress to the fish. Take alook at night when the lights are off at 3;00 am in the morning, I see night owl fish swimming around invading other fish territory, sometime in effect to cause fights, I've seen fish dart about when this happens, sometimes they all sleep through the night without any problems. There's lot to wonder about. Regards Ken