How many hours should the aquarium lights be on?

[vipvenom]

I have a dual PC on my 29tall. I run the lights on seperate timers. The 1st comes on from 8am - 8pm and the second comes on at 10am - 10pm. Is 14hours too much light for an aquarium? How many hours are your tanks lights on?

 

[r6mason]

I was told that marine fish are use to 12 hours with light and 12 hours without. But I am not sure how true this is. I run my lights about 13 hours

 

[Guest]

I usually have problems with algae if I go longer than 11 hours. I don't have a reef though
actinic ON 1pm
10k ON 2:30pm
10k OFF 10pm
Actinic OFF 11:15PM

 

[steve-s]

With PC or other HO fluors, you can run them a fair amount without negative impact an the inhabitants. MH on the otherhand should be around 10 hrs/day, too much can cause problems. Fluorescents are not intense enough to be a concern in that regard.

Cheers
Steve

 

[vipvenom]

Good to know about the lighting. I switch my timers to run 13hrs a day instead of 14hrs, mainly so I can sleep lol. If light becomes a problem what are some of the symptoms? Rapid algae growth as someone mentioned?

 

[austinsdad]

If light becomes a problem what are some of the symptoms? Rapid algae growth as someone mentioned?

Yep.

 

[steve-s]

Lighting is almost never the root cause of nuisance algaes, excess nutrient/phophorus is. You should be able to run HO flour lighting for 15 hrs/day without issue.

Cheers
Steve

 

[vipvenom]

Well as of right now I haven't had an algae problem. I was just wondering if it was going to affect my fish or inverts at all.
If I were to start to do some easier of the corals would I need to follow a different lighting schedule or is my current 13hr a day sufficient?

 

[MT79]

If I were to start to do some easier of the corals would I need to follow a different lighting schedule or is my current 13hr a day sufficient?

13 hrs would be more than sufficient. 12-14hrs daily is a fairly standard photoperiod w/ fluorescent lighting.

 

[MarineFlake]

Couple notes from experience...on my 29G I run the 03's for 8 hours and the MH for 6 hours. On my 75G I run the same schedule. However, as the VHO bulbs on my 75 age, I do notice an increase in algae and a decrease in the health of the corals. They are replaced every 6 mo. 2 03's and 2 10k's. Its a softie tank with a galexea (tooth coral) at the top. Everyones happy.

GL!