# Lighting Schedule



## roeguy (Oct 1, 2008)

Hi everyone, I've been using a 65W power compact over my 28 gallon lightly planted bowfront for a couple of weeks and turning it on and off manually.

Today i bought a digital timer that lets you program up to 20 on/off settings.

During the week, I leave for work from 8:00 to 5:30. I would like to program the lights to turn on at say 7am, then turn off at 11am, then turn on at 2pm and stay on until 11pm. This would give a total of 13hours, and give the fish 8 hours of relatively pitch darkness.

Questions are:

a) is this ok for the fish
b) is this ok for the plants
c) will this reduce the life of the bulbs
d) will doing this reduce algae (I read people claiming that turning off lights during the day for a couple of hours stiffles algae growth, but not plant growth)


----------



## bluekrissyspikes (Apr 16, 2009)

i think with the amount of hours the light will be on it will cause algea problems. if you are not home during the daytime and you want the lights on in the evening when you are home i'd set them for then, but try not to go past eight hours. it's a lot easier to prevent algea than to get rid of it and you have fairly high light


----------



## redclove (Feb 26, 2008)

I've often wondered about this too, is it not stressful to the fish to have two light periods during the day? (on/off/on/off) It seems unnatural..


----------



## xr8dride (Feb 24, 2009)

Very unnatural indeed, imagine how our bodys and such would react to two schedules of day & night....I hardly get thru one day never mind two in one day, lol. I also suggest a max of say 8 hrs continual light, when home so that you can enjoy the view.


----------



## redclove (Feb 26, 2008)

yeah def. unnatural for humans, but I wonder about fish.

For 8 straight hours it doesn't work too well, I get viewing only in the evening when I'm chilling in the living room. lights dont turn on until noonish and I'm gone to work by then. It would be great to see them lit in the morning and the evening. Do fish dig siesta's is the question..


----------



## roeguy (Oct 1, 2008)

Well, first of all, I am not quite sure how much total time lights should be on per day. 8 hours seems low. It is a planted tank after all, and plants like light 

About turning off the lights during noon time, the room won't be pitch dark. So in terms of relative lighting I would imagine it would be like this:

11pm-7am = near pitch darkness getting gradually brighter
7am-11am = lights are on, maximum brightness
11am-2pm = lights turn off, low ambient light
2pm-11pm = lights are on, maximum brightness

in nature, it is rare that you get continuous uninterupted sunlight. Clouds do obscure the sun, so I would imagine fish don't need to have a steady concentration of light throughout the day.

The big problem with fluorencent lights in my opinion is that they cannot be dimmed, or gradually made brighter. So its kind of a shock. I wouldn't enjoy waking up to a bright light.


----------



## redclove (Feb 26, 2008)

roeguy said:


> Well, first of all, I am not quite sure how much total time lights should be on per day. 8 hours seems low. It is a planted tank after all, and plants like light
> 
> About turning off the lights during noon time, the room won't be pitch dark. So in terms of relative lighting I would imagine it would be like this:
> 
> ...


yeah something like that would be great. an I suppose you could do an LED system on a separate timer with white LEDs to mimick a medium light, and just ramp it up a little to full light.


----------



## Calmer (Mar 9, 2008)

roeguy said:


> Questions are:
> 
> a) is this ok for the fish
> b) is this ok for the plants
> ...


Answers are:

a) my guess is if there is enough ambient light in the room then the fish will still be awake and it would feel normal to them like a cloudy intermission between the two light periods. 
b) probably as plants do adapt very well. 
c) yes but you won't notice that much of a difference with regular normal output florescent lights.
d) never heard of that before but I like to believe it is true.


----------



## redclove (Feb 26, 2008)

hmm I stil want to try this, opinions are mixed so far. anyone else with thoughts?


----------



## roeguy (Oct 1, 2008)

From: http://www.fishchannel.com/fish-health/freshwater-conditions/aquarium-freshwater-algae.aspx

Controlling Algae: Lighting
The relationship between lighting and algae is complex. In an unplanted aquarium, the more light you provide, including direct sunlight, the faster algae will grow. But because many aquatic plants can actively suppress the growth of algae when they are healthy (see Allelopathy below), brightly lit aquariums with a lot of aquatic plants can actually have less algae than dimly lit aquariums with no plants or only slow-growing plant species.

Controlling the lights' illumination period in an aquarium is important. Aquatic plants do best with a regular 10- to 12-hour lighting period. Any lighting beyond this point will favor the algae. *Aquatic plants do just as well if the lighting is broken into two five- to six-hour periods with a two-hour "siesta" in between, but for some reason, algae do not.* Try putting your aquarium lights on a timer switch to see if that reduces algae problems in a planted aquarium.


----------



## Calmer (Mar 9, 2008)

Thanks for the link, roeguy. I definitely will be splitting up my lighting cycle into two periods once the Smart Metering System starts. I will be lighting the tanks in mid peak time. See pie chart in the below url:
http://www.hydroonenetworks.com/en/community/projects/smart_meters/Smart_Meters_Answer_book_ENG.pdf


----------



## Chris S (Dec 19, 2007)

roeguy said:


> *Aquatic plants do just as well if the lighting is broken into two five- to six-hour periods with a two-hour "siesta" in between, but for some reason, algae do not.* Try putting your aquarium lights on a timer switch to see if that reduces algae problems in a planted aquarium.


From what I recall, this is because algae works like an on/off switch. Light is on, algae is photosynthesizing. Light is off, algae isn't!

Plants are more complex though and will continue to use nutrients (ammonia, nitrate, co2, phosphate, etc.) for a period after lights are off.

So having up to 1 hour "siesta's" helps give your plants an edge.

This, of course, only applies when there is actually enough nutrients to be used.

As for the effects of breaking up your lighting schedule on your fish - I've never noticed any, which includes some successful breeding. I wouldn't be concerned.

I run some weird light schedules as well:

6am - 7am

12pm-2pm

5pm - 11pm

co2 kicks in a half hour before the lights turn on and turns off a half hour before the lights turn off.


----------



## JamesG (Feb 27, 2007)

The only benefit to turning the lights off for a siesta would be the confuse the hell out of your fish and convince any 'daylight length dependant' species from reproducing. Of course nobody out here wants to do this. 

I agree with Chris that the plants can still be using nutrient in the absence of light, this is called photorespiration. However, the real benefit to large plants versus algae is that the large plants can have more stored nutrient (assuming there is enough around for them to store) based on their size than a single cell algae or even a more complex algae. 

I cannot see this siesta being healthy for your fish that depend on day length to determine the season. This is true for most mammals and birds I believe but fish I am not 100%. I choose to err on the side of caution. 

Short of putting up a picture as proof of my algae free 210 gallon you guys will have to take my word for it that I have no algae aside from a bit on the glass with my lights running for about 13 hours per day. 

I think a large problem with algae is not the photoperiod it is the fact that if you choose to feed your fish twice a day, one of these times being when the lights are off, the fish just don't eat the food because they are in their pseudo sleep state. This uneaten food is of course a perfect nutrient source for algae.


----------

