Do fish need light??

[FishLover01]

I would be concerned more about the changes in salinity due to evaporation. It's always possible your equipment could fail or there could be a power outage while you're away and everything stops working. Really need a person to check on the tank every couple of days.

 

[007Bond]

I use these timers > http://www.ebay.com/itm/Hydrolux-Du...0&pid=100005&rk=4&rkt=6&sd=331651511580...off /on 8 x per day. I have half a dozen on my system...lighting, dosers, pumps, skimmer ect. cheap and easy to set up.

 

[Bruce Burnett]

your fish will be fine without lights, it will slow your fish down and won't need as much food. It will also reduce water evaporation.

 

[Kungpaoshizi]

Fish should be fine, but try to open windows/etc to let some light in.
https://en.wikipedia.org/wiki/Circadian_rhythm

 

[mkj]

as long as daylight is in room fish are fine. Water evaporation is your biggest problem