- Joined
- Jan 18, 2008
- Messages
- 569
Nocturnal cephalopods (or at least O. mercatoris) don't appear to see red wavelengths very well and therefore will think it is essentially "dark" and go about their business as usual when no lights are on in the room and you only have a red light in the tank. This allows you to see them quite well as they go through their normal nocturnal activities anywhere in the tank instead of the inconvenience of using a red flashlight and having to hold and point. It would be even less convenient if you had to shine a white flashlight around the tank at night and ended up scaring them back into hiding.
Here's an example of our merc tank:
Here's an example of our merc tank: