Newbie with a fungus problem?
No. Goldfish are not nocturnal. Maybe the previous owner used to feed them right after lights out or something so they have Pavlovian conditioning to start looking for food after lights out. Check with the previous owner. If it’s Pavlovian, they will slowly learn that you don’t feed after lights out and they’ll start to change their habits. I’m guessing that the external environment probably changes a little when the tank lights are out so things look different to them so maybe they get a little more interested in what’s going on in the room.
A few years ago, we had this discussion in a forum about whether the fish can see as well out of their tank when the tank’s lights are on. For example, if you are in your home and it’s darker outside than inside, the glass forms a mirror effect so you can’t really see outside very well. If you turn off the lights inside, then you can see outside much better. I’m not sure if this same effect happens when the water is directly against the glass. I do know that when looking at the side panels of the tank at an angle from the front glass, they become mirrors of the back of the tank when the tank lights are on but when the tank lights are off, if you look from the front of the tank through the side panels, you can see through them rather than get the mirror effect.
I used to scuba dive in my younger years and volunteered in our public aquarium and remember being able to see the people outside the tank but I also remember some mirror effect. I know my fish can see me when I’m in the room as they will stalk me for food.. lol.. but I still think they can see even better when their tank lights are off and the room lights are on, compared to when the tank lights are on and the room lights are off.
Lenny Vasbinder Fish Blog - http://GoldLenny.blogspot.com (Links to any articles referenced in above reply are listed on the right side, alphabetically under Labels and also under Archives by Year, Month)
Category: Philippines Internet Koi Society
