Lighting question

[KenFromBG]

I have 2 tanks, both have LED lights with automatic settings. Both go to a soft blue light at night. I read somewhere else that you dont want any light at night and fish need total darkness. Do I need to change my light? (I dont want to, my lights were expensive)

 

[PheonixKingZ]

What model/brand of lights are they?

It is true that fish need multiple hours of total darkness, so blue lights at night are bad for them. (I wouldn’t really say “bad”, but they definitely aren’t “good”)

 

[andreisdabest]

I used to leave my tank on blue, but the fish stll went around the tank dooin' their thing like it was on white. I dont leave it on anymore

 

[Byron]

The short answer is you need to have total darkness--in the tank and in the room--for a period of several consecutive hours during each 24-hour period. Fish need this to maintain their circadian rhythm and this has a considerable effect on their physiology, metabolism and well-being. You can find older threads where I detail why, or I will repeat if asked. But there is no doubt whatsoever that aquarium fish will be better off (= healthier) with a period of complete darkness.