Aquarium lighting vs ambient light

Shilpan

Member
Ok I've been thinking about my aquarium lighting schedule since I've got this fairy wrasse since he sleeps the moment the lights go out.

Basically we like to see the fish at night when we get home. So I usually start the lights at 4pm and finish at 10:30pm (my schedule is only 6hrs atm to combat cyano which is going well!).

Now before hand from 6-7am the fish get some ambient light from the light coming into the windows (not direct of course). My question is does this matter? Does this ambient light really make a difference in terms of

1) algae growth?
2) fish sleeping cycle?

Because if it does then I should be turning on my lights at 7am and off at 6-7pm when the sun goes down shouldn't I?
 

one-fish

Active Member
Hey Shilpan, Still fighting the brown and red stuff here too. Doing the same playing w/the light freq. leaving sump light 24/7 washing all foods w/rodi. If you think ambient light is detrimental try covering tank or blocking light from window, dont think fish care when the lights are on or off,, but I am not a fish...
 

iidylii

Active Member
to my knowledge as long as its not direct sunlight it should have no affect on algae...

as far as fish sleeping...regardless of what my lights are set at my fish wake up as soon as the room has any type of light from windows or house lights or what have you...
 

Shilpan

Member
Hmm I see! Yeah my clowns and bangaii wake up with any type of light too, but not my wrasse, he waits I'll 4pm for the tank lights, until then he hides in his rock.

Oh ok in that case, it sounds like starting my lights late in the day and finishing at 10:30 at night should have much impact on my tank really. Just gives the fish a reduced night time. But surely 10:30pm-6-7am is enough sleep for them
 

Shilpan

Member
By the way one fish there's some really weird stuff happening with my cyano. Since I reduced lighting in the display and made refugium 24/7,

-the cyano on the rocks has slowed growth,
-it's started growing on the glass and sand only now (and again really slowly)
-my GHA stopped spreading, so I'm picking it out every weekend to get it out before it dies
 

deejeff0442

Active Member
As long as you keep.water in parameters the algae and cyno go away. Nature takes time. New tank blooms always happens .
Like you guys figured out this is not a speedy hobby
 

geridoc

Well-Known Member
Hey Shilpan, Still fighting the brown and red stuff here too. Doing the same playing w/the light freq. leaving sump light 24/7 washing all foods w/rodi. If you think ambient light is detrimental try covering tank or blocking light from window, dont think fish care when the lights are on or off,, but I am not a fish...
I don't think you should be leaving the sump lights on 24 hr/day. Photosynthesis has 2 phases, a light phase during which light energy is captured into high energy compounds, and a dark phase during which the captured energy is utilized to synthesize organic molecules. You need both to produce good growth (and nutrient export). Most people who illuminate their sumps use a light cycle exactly opposite to whatever cycle the display is on so that the carbon dioxide (and acid) that are produced in the display is captured and converted in the sump, and vice versa.
 

Shilpan

Member
Hey Geridoc! Yeah I agree with you because that's what I always learnt at uni too.
I've had a reverse photoperiod for the past 2 months. I switched it to 24hrs on suggestion from 2Quills after I trimmed too much macroalgae off and I also have a cyano bloom going. I've found the macroalgae growth has exploded and it's my cyano battle is slowly starting to tip in my favour. Not sure if this is due to the refugium or tank maturity (I have coralline popping up), but it's definitely increased my macro growth and I don't really understand why..?
 

2quills

Well-Known Member
It's because you don't need a dark period for respiration to happen. I think the confusion comes into play because the dark period happens in nature so people tend to assume some darkness is necessary.

24 hour light cycle isn't a issue unless you're outgrowing certain limiting factors like co2 and nutrient.

Otherwise, someone needs to tell my chaeto it shouldn't be growing as good as it does under 24 hours of light.
 

Shilpan

Member
Actually another thing, I learnt that most plants like land based plants need the dark period to grow and regenerate certain compounds overnight. But this may not apply to algae in exactly the same way either.

Lol yeah my chaeto and caulerpa is now following yours 2Quills :D actually I think 24/7 is what most people do for caulerpa anyway
 

2quills

Well-Known Member
Yeah that could be another factor as well. Algae are unicellular organisms, less complex than terrestrial plants.
 

one-fish

Active Member
By the way one fish there's some really weird stuff happening with my cyano. Since I reduced lighting in the display and made refugium 24/7,

-the cyano on the rocks has slowed growth,
-it's started growing on the glass and sand only now (and again really slowly)
-my GHA stopped spreading, so I'm picking it out every weekend to get it out before it dies
Shilpan, How you doing w/ the cyano is light reduction helping? I am in day two of black out of DT running sump light 24/7 had to remove chaeto was dying off. Cyano in DT looks as its dying off but brown bubble algae now spreading thru out sump. See you were making progress just wanted to touch base to see if it is working . Thx
 

Shilpan

Member
Hey One-fish! So ive reduced the lighting to 6hrs, but put it back up to 7hrs today. Cyano growth has slowed (I take pictures before water changes and compare how much cyano grows in my tank every 2 weeks), but the reduced lifting isn't killing it.

I think the reasons it is slowing are mostly due to my 23.5hr refugium lighting (macroalgae is growing despite undetectable nitrates meaning it's competing with microalgae), and the fact that I'm siphoning it off. I expect two to four more months of cyano growth because from what I've seen that's how long it takes most people with dead rock to have their rock stop releasing nutirients from die off.

I siphoned off more cyano, I'm resting phosphate now to see if I need to change my GFO, and I'll let you know if the cyano growth slows any more by next week.
 

one-fish

Active Member
My P04 level is <.25 ppm kinda high (don't have a good low range test) Going to continue black out and watch cyano, some GHA I can live w/but red slime. Going to add more snails to my CUC
 

one-fish

Active Member
Well just turned lights back on from three day black out (company coming over) I know that the cyano will come back but it's nice to see it almost gone Learned one thing what works for some doesn't always work for all so research and experimentation is the key. Seeing alot of brown algae with small bubbles covering the sump and everything in it and this has given me an idea. Thx.
 

Seahorsebill

New Member
I don't think you should be leaving the sump lights on 24 hr/day. Photosynthesis has 2 phases, a light phase during which light energy is captured into high energy compounds, and a dark phase during which the captured energy is utilized to synthesize organic molecules. You need both to produce good growth (and nutrient export). Most people who illuminate their sumps use a light cycle exactly opposite to whatever cycle the display is on so that the carbon dioxide (and acid) that are produced in the display is captured and converted in the sump, and vice versa.
I don’t know much about macro algae I’ll be the first to admit that but I have grown lots of marijuana (legally may I add). Marijuana has two light cycles (24 hours on) vegetation state. They just grow grow grow and do not flower. Then there’s 12/12 (12 hours of light. 12 hours of darkness) as soon as you switch from 24 to 12/12 you plants bud and you leave them on 12/12 until they are ready to harvest. Once harvested you can cut buds off and then you switch back to 24 hour lighting and the plant will return to vegetative state.
i fugure macro algae would work same way since it photosynthesis. So in theory leaving your lights on could help your algae to grow. And if I understand right you plants release Co2 back into your water at night. So this could eliminate high levels of Co2 in the tank. IDK?
Not trying to come off as a plant expert. Just saying what I know to add to the discussion and hear what the rest of the forum has to say.
 

Seahorsebill

New Member
Ok I've been thinking about my aquarium lighting schedule since I've got this fairy wrasse since he sleeps the moment the lights go out.

Basically we like to see the fish at night when we get home. So I usually start the lights at 4pm and finish at 10:30pm (my schedule is only 6hrs atm to combat cyano which is going well!).

Now before hand from 6-7am the fish get some ambient light from the light coming into the windows (not direct of course). My question is does this matter? Does this ambient light really make a difference in terms of

1) algae growth?
2) fish sleeping cycle?

Because if it does then I should be turning on my lights at 7am and off at 6-7pm when the sun goes down shouldn't I?
What I did was went to fabric store and bought a piece of black felt. Walmart has it. Then I bought some Velcro with a sticky side. I stuck the Velcro onto the back corners of my tank (I only have three corners total cause I own a 54 gallon corner bow front aquarium). I sewed the Velcro onto the felt. When I turn the light off in my aquarium I cover the front of the tank with the felt and secure it with the Velcro. I also have a piece I put over the top of my tank. This why when the lights go out on my tank I can be assured my fish are not bothered by ambient lighting and I don’t have to stumble around in the dark cause I keep my aquarium in the livingroom and we work midnight so we sleep from 8 am to 3-4 pm
 
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