Why do fish die at night?

Just one of those philosophical questions I have always asked myself but figured there might be good reasoning behind it. Any thoughts?

 

Hypoxia.

 

whats that

 

Lack of oxygen

 

Why is there less oxygen at night?

 

because of a change in pH and water temp

 

Unless you have a fuge that is lit opposite of your main tank, then the lack of photosynthesis causes less O2 to be available at night.

 

Yep. Many people over stock their tanks. Has nothing to do with filtration, it is how much O2 salt water can hold. The higher the salinity and temp the lower O2 saturation is.

While skimmers and powerheads can help oxygenate.... the majority of O2 comes from photosynthisis and tanks can become hypoxic at night. In fact natural reefs can be hypoxic at night.

Now I have no idea if that is what you are really asking about or that is what happened... but if you want to know in general... then that is my guess.

 

Really just a general question haven't had any casualties in a while but you read so many posts that say this fish was dead by morning or went missing that morning indicating that it all occurs over night

I figured there was some reasoning behind it

 

I didnt know .good question