Fish And A Day/night Cycle Help

[Spishkey]

ok bit of a strange one but do fish have a day/night cycle like animals and humans?

reason im asking is for the past 6 months i have kept my fry/corydora tank in the boys bedroom, and as well as them enjoying watching it, they have used the tank as a big expensive night light. so the light has been on all night, and the room kept dark in the day.

Now the boys have decided they dont want the fry in there anymore, they want to pick there own fish (MM platys to be exact!) so i want to move the fry into the kitchen and move the platys to their room.

but i dont want to 'shock' the fish by switching their day/night routines if they have them?

is it safe to do a straight swap of tanks or do i have to slowly make the light change? ie. a few hours more dark here, few hours more light there, until its switched from what they are used to?





you all think im crazy now.....

 

[bricko]

Hi Spishkey,

I am no expert on animal welfare but I can give you my experience from the past, have accidentally left lights on overnight.

As soon as the error was discovered (the next morning) the lights were reverted to their usual cycle 12pm - 10:30pm with absolutely no noticable adverse affects. Having said that it was a one off occassion and the worst it could have done was interupt the fish's sleep for 1 night and encouraged a bit of algae.

If your fish have been used to a certain routine then it may be better to aclimatise them to the new setup.

Personally I would just set them up in there new environment with no lights on for the first few hours the flick them on once the fish have settled (just as you would when first purchasing) then let the lights go out at the usual (new) time and begin the cycle in full from the next day. I don't believe they will take much getting used to the new regime as long as the food keeps coming.

Cheers,

Bricko

 

[Corleone]

Fish do have a day/night cycle. If the room is kept dark (drapes pulled so there's no daylight either, though I don't know how much that would matter), it should be possible to switch them to be up at night like this, just like household pets usually adapt to be active when their owners are up and the lights are on, but they might be jetlagged by it at first. Many fish are imported from radically different timezones, and are just dumped into local time without serious issue, this would probably be no difference.