Now betta will survive the night with the filter off but you are harming the biological filter itself.
Do you turn betta fish light off at night.
However just like their wild cousins captive betta fish do need to sleep at night.
With all due respect guppies4life ive seen you say 16 hours before when advising on light hours 8 10 is about right someone running at 14 16 as ive seen you say will more than likely cause algae problems at some point.
As for the filter.
Simply set the timer to turn the light off at the same time each evening and to turn it back on the next day.
So you must turn out the tank lights overnight to replicate the natural day night cycle that the fish enjoy in the wild.
Betta fish typically need 8 to 12 hours of light and 12 to 16 of darkness so make turning off your tank light a pre bedtime habit.
And the most important things you need to remember are.
Yes you should turn the light off you re never giving your fish a chance to sleep if you don t keep the light 8 14 hours a day that s what i do.
The easiest way to do that is by turning the tank light on when you get up in the morning and switching it off when you go to bed at night.
You ll see this stress play out in feeding habits mostly.
You can keep female betta together but you need large tank and a decent group of fish 5 to spead out any aggression.
And of course the answer is off.
Now you should have a solid understanding of whether to leave a betta fish light on or off at night.
Some bettas won t eat at all when stressed by too much light.
Too much sunlight can overstimulate your betta causing stress and agitation as well as possibly causing feeding problems.
Always best to leave it running.
Basically it plugs into the wall and then plugs into your aquarium light and it switches the light off at your certain set time everyday.
Consistent light cycles that replicate daylight and nighttime reduce stress and mimic natural environments.
Here is a picture of some.
Also a cheap appliance timer may do the trick if your bulbs don t eat up too much power.
If you don t want to use light timers set an alarm and turn the lights on and off at the same time each day.
If you don t want to go this route you can use alarms to remind you each day as to when to turn the lights on or off.
These light timers are probably the most effective and easiest manner of replicating your fish s night and day cycle.
And yes you should turn your lights off on a regular schedule.
One becomes dominannt and keeps picking on the weaker one until it dies.