Day Vs Night setting

bettaguy

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Anyone else have a night time setting? Not for the whole night but for a little while when you want things dark?
 

Mark.A

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I used to have my last one go to blue for a while but the red and blue looks better! Will try that when I get the tank I’m just setting up sorted.
 

Tim Harrison

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Outside the photoperiod my light is on but somewhat dimmed, only enough to view the tank and appreciate the colours of the plants and critters. Obviously it goes off completely at bedtime :)
 

Oldguy

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but the red and blue looks better

Outside the photoperiod my light is on but somewhat dimmed

Surely red/blue light is utilised by the plants for photosynthesis, so the photo period is just extended. It may look dim to our eyes because we see better in a yellowish light. To humans a cold light is not as 'bright' as a warm light. I use red/blue LEDs for my 'high noon' lighting for plant growth, I assume the fish see it as just a brighter light compared with the lighting used for most of the photo period and slip into the vegetation.

Would I be correct in thinking that fish 'see' in a much wider spectrum than we do. I can understand a blue light being used to represent light in very deep water but not as a night colour.

For dawn and dusk I just use very low powered and hence 'dim' light lights.
 

Tim Harrison

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Surely red/blue light is utilised by the plants for photosynthesis, so the photo period is just extended.
Not really, it's too dim. I doubt it's even anywhere near the light compensation point, for instance.

Would I be correct in thinking that fish 'see' in a much wider spectrum than we do.
The goldfish Carassius auratus has tetrachromatic color vision it can see in the red, green, blue, and UV regions of the spectrum.
 

Tim Harrison

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Does this apply to other fish, or is there little or no research on other fish species.
I think it's probably more common than was thought to be. Apparently a wide range of fish species posses this adaptation https://en.wikipedia.org/wiki/Vision_in_fishes

What about growlux tank lights and their equivalents in LEDs as used in hydroponics. These match the photosynthesis absorption spectra. Its dim to us but is it dim to plants.
I think spectrum matters to lifecycle and growth morphology, any white light is full spectrum, as far as plants and humans are concerned. The photosynthetically active spectrum and the visual spectrum are one and the same give or take a few nm; a happy coincidence of evolution.

I think it's best to choose a light you like the aesthetics off, since that's really the whole point. Growlux type lights are far too pink for my liking.
 
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