Can you run photoperiod different at weekend?

[Kevin Eades]

Would there be a detrimental effect on having different lighting schedules on different days? I have my lights running 1-9pm. But on a weekend I would prefer to run something like 10am-6pm so I can enjoy more of it during the day. Cant change it on weekdays 10-6 as I will only see the lights on for an hour that way.

 

[Tim Harrison]

Plants don't just respond to the actual photoperiod, research shows they anticipate it. Regularly changing timing of the photoperiod could mess with their cicardian rhythm. It's probably something few folk have done but I guess you could always give it a go and see what happens. Close observation would be key in case it all starts to go Pete Tong.

Role of circadian rhythm in plant system: An update from development to stress response

Plants have internal timekeeper known as a circadian clock that anticipates environmental cues such as light, temperature and regulates photoperiodic …

www.sciencedirect.com

 

[Paul Kettless]

I was watching a video the other day by Jurijs Jutajevs, I think he was showing a controller for the Twinstar 900s or 1200s not sure now, and how you program it.

He suggested that by ramping up the light from only 3% power it would not be enough light to start the photosynthesis process, but enough to enable adequate viewing. Nor sure how true that is, and didnt really question what he was saying. Obviously this would be very difficult to mimic as would need to have exactly the same size tank, light and the ability to adjust the power by increments of 1%.

 

[Paul Kettless]

twinstar controller - Google Search

Managed to find the video, is actually a Twinstar 1200sp. Still might be of interest thought to you.

 

[Kevin Eades]

Plants don't just respond to the actual photoperiod, research shows they anticipate it. Regularly changing timing of the photoperiod could mess with their cicardian rhythm. It's probably something few folk have done but I guess you could always give it a go and see what happens. Close observation would be key in case it all starts to go Pete Tong.

Role of circadian rhythm in plant system: An update from development to stress response

Plants have internal timekeeper known as a circadian clock that anticipates environmental cues such as light, temperature and regulates photoperiodic …

www.sciencedirect.com

I am thinking of setting up a tank to keep plants before a rescape and as a hospital/ isolation tank so I may give it a go on that. I also have some nicrew lights and they have a 24hr cycle. I've not used it as I think it stays too bright for too long in my opinion with only a few hours in total darkness. The plants don't seem to mind but the fish never seem to be resting

 

[oreo57]

Would there be a detrimental effect on having different lighting schedules on different days? I have my lights running 1-9pm. But on a weekend I would prefer to run something like 10am-6pm so I can enjoy more of it during the day. Cant change it on weekdays 10-6 as I will only see the lights on for an hour that way.

Yes, I'd probably not mess w/ he circadian aspect of it.. Like if you worked 1st shift for 3 days, second for 2. Think it would mess w/ your body a wee bit.
I'd prefer to run it 10-9 w/ reduced output so that the DLI (cumulative daily photons so to speak) is equal.

As a crude example if you provide 30 PAR for 8 hours 20 PAR for 12 hours is equivalent.

Free Daily Light Integral (DLI) Calculator - ScynceLED

Check your Daily Light Integral with our free DLI Calculator to gain insight on how much light is available for your plants.

scynceled.com

Plants will adjust to the 12 hr after awhile.

 

[Kevin Eades]

Thanks all thought there would be issues. But if you don't ask you'll never know😃

 

[Snowstreams]

I was watching a video the other day by Jurijs Jutajevs, I think he was showing a controller for the Twinstar 900s or 1200s not sure now, and how you program it.

He suggested that by ramping up the light from only 3% power it would not be enough light to start the photosynthesis process, but enough to enable adequate viewing. Nor sure how true that is, and didnt really question what he was saying. Obviously this would be very difficult to mimic as would need to have exactly the same size tank, light and the ability to adjust the power by increments of 1%.

I have been doing this with my tank but with more like 5% intensity until the afternoon then I go full power until the evening.
But I was taking ph readings to see what my co2 levels were like before I started injection.
It looks like my plants were photosynthesizing on the 5% light or at least my algae was because ph was rising quite a lot.

I've co2 injection now but I want to experiment with an afternoon nap. But I guess that would totally affect the plants circadian rhythm.
What affects would the plants get if their rhythm is off?

 

[zozo]

What affects would the plants get if their rhythm is off?

In aquatic form plants, I guess the effect won't be so drastic... In terrestrial form, this can be different, but only for annual flowering plants but not so much for perennials and evergreens. Then the effect would rather be obvious with plants below or near every light pole in the street.

For annual flowering that depends on seasonal circumstances such as light hours for growing or flowering it's much more important. When a plant is in the flowering season mode it actually reduces the vegetative growth in size such as stem length to put energy in the flowers or fruits. If it gets too much extra light when in the flowering mode it gets disturbed and confused and doesn't know any longer what to do, then it will do both make flowers and keep up growing vegetatively in size. You could compare this with a form of etiolation with less compact and smaller flower buts or fruit with longer stems in between. This you can experience with annual flowering near a street light or an automated floodlight in the garden.

Plants that do not carry flowers don't care much for it, see also, for example, your houseplants, these next to the plants in the lit streets are in the worst circumstances regarding light and circadian rhythm you can imagine because we switch the lights on and off whenever needed. Yet I need to see the first one suffering from it.

Not saying that this goes for all, I guess the ones that are sensitive to it can't be kept indoors in pots... There are more we can't keep than we can keep.

Since we have no flowering annuals in our aquariums, you could consider them houseplants... And it's trial and error, If they get light > than their LCP they will naturally utilize it and grow.

For fish, it would be a different story... I guess they are much more sensitive to it.

 

[Snowstreams]

Thanks that reminds me of a few birch trees I've seen near me that still have green leaves on their sides that are near some spot lights.
My main concern in my tank is algae on my plants leaves. So I want my plants to grow faster than the algae hence I recently added co2.
My 9 year old son gets up early (6:30) every morning and he turns on this 2w led light to see the fish. Then I time the main light to come on at 8 and go off at 11 along with the 2w light.
Then at 3pm he comes home from school and lights are all back on full power until 8pm.
School will be finished for a few weeks so I suspect the 2w light will be on most of the day now feeding the algae!
Is there a special bulb that doesn't feed algae? I'm guessing maybe a low powered green led could work?

 

[zozo]

I have played a few years with LED controllers to lit the tank 24/7 12 Hours within the LCP and 12 hours outside the LCP as moonlight... I actually never noticed any negative effects on the plants... And if the room is fairly dark you still have a good view of what is going on in the tank. And i did it with white light, which looked the best of all colors.

That LCP is a bit of a guess without data and measuring equipment... Regarding data, I remember a paper listing a collection of aquatic plants and their LCP. I know it's out there somewhere but lost track of it...

Thus that again is trial and error... For me, it seemed to work out fine and rather liked it... How far you need to dim the lights for that depends on the lights... Back then I could go down to 2% intensity and still could see all rather clear. The very dim light breaks the mirror effect of the glass if the light outside the tank isn't brighter.

I don't know about more modern LED controllers I did it with the TC420 which has software able to schedule a dim from 1% to 100%
The newer TC421 has a crappy software update with a number of limitations, not recommendable...

 

[Zeus.]

Any extend phot period beyond what your plants need is for your pleasure only and algae will use that light, so its s bit of common sense and 'suck it and see'. I did program my PLC for extended viewing times with low light intensity at the push of a button which worked well and one of my favourite viewing times was the Moonlight passover phase I did on my 500l

 

[Wolf6]

I was looking for information on when planting do most growing (night morning etc) and found this on an old thread here. Biologists Identify Genes Controlling Rhythmic Plant Growth - Salk Institute for Biological Studies
Reading that makes me believe messing with the regular rythm wouldn't be very advisable. Of course its open to interpretation and you can always try, but if anything id go with the siësta option to have a longer day that way, but have the same pattern of lighting everyday instead of changing it for weekends.

 

[Zeus.]

Reading that makes me believe messing with the regular rythm wouldn't be very advisable

You could always do a low intensity period/timings to match the local full moon period, that way you would just be reproducing a more natural environment, however to match it the extended viewing periods may be in middle of the night eg 1am to 3am. Having done specimen fishing trips for 4 day solid day/night when there's a full moon in the middle of nowhere with no light pollution it surprising how light it is with a full moon

 

[zozo]

If you are growing Anubias you can do a Blackout experiment for 7 days... And notice a lot of new growth on the Anubias that grew during this dark period. I guess that's why they named this plant Anubias after the Egyptian god of the underworld...

Nymphaea is also such a plant that can show significant growth bursts during the night... Or moving all its floating leaves from one side of the tank to the other overnight. That's a remarkable thing to observe...

Plants definitively store energy and use this to grow or move during the night.

 

[dw1305]

Hi all,

but if anything id go with the siësta option to have a longer day that way, but have the same pattern of lighting everyday instead of changing it for weekends.

That is what I do, usually the home tanks have a short siesta, so that they are light when I'm home in the early morning / evening. At the weekend I just change (override) the time switch so they remain on during the early afternoon. It means the tanks get 13 hours (07:30 - 20:30) of light on the weekend, but that doesn't seem to matter.

cheers Darrel

 

[Wolf6]

Hi all,

That is what I do, usually the home tanks have a short siesta, so that they are light when I'm home in the early morning / evening. At the weekend I just change (override) the time switch so they remain on during the early afternoon. It means the tanks get 13 hours (07:30 - 20:30) of light on the weekend, but that doesn't seem to matter.

cheers Darrel

Ive done that with my youngest sons low tech tank and ive done it with a previous setup of my own, works fine with siësta, never had serious algea with either that way. I can recommend that way. I feel, but have no proof, that the 'sunrise' moment (moment when plant can start photosynthesis) is the most important to keep steady.
These days I just have multiple tanks so there is always something to view and i dont have to puzzle😆

 

[kayjo]

I was watching a video the other day by Jurijs Jutajevs, I think he was showing a controller for the Twinstar 900s or 1200s not sure now, and how you program it.

He suggested that by ramping up the light from only 3% power it would not be enough light to start the photosynthesis process, but enough to enable adequate viewing. Nor sure how true that is, and didnt really question what he was saying. Obviously this would be very difficult to mimic as would need to have exactly the same size tank, light and the ability to adjust the power by increments of 1%.

That's my approach too. By ramping the light up to the photo period and back down again I am able to have my lights on for 12 hours without algae problems. This gives me a long 12 hour viewing time and the plants get 6-8 hours of useful light. The ramping up and down provides plenty of light for the human eye to enjoy the tank, but not enough or much for plants / algae. I also like the way the tank's appearance changes throughout the day.

It helps having a programmable light with known PAR values.