Is 390nm-400nm light useless ?

[Lobophyton]

Hi, i have a led strip (390nm-400nm) when using alone it make some coral fluorescent green. Pipe organ coral polyp turn green, i've never seen it green under my blackbox light.
Hammer coral polyp are completly fluorescent. Water have a green tint.

is it useless ? thx

 

[Hurricane Aquatics]

No, it isn't useless. It is useless by itself for overall coral health, but when mixed in with other spectrums, it is needed.

 

[jda]

It can do three things. It can provide energy by being directly absorbed. It can be used partially with some light expelled at lower energy wavelengths - this expelled light is often a very deep violet. It can build a type of sunscreen pigment in corals. These last two things can provide some color that other spectrums cannot.

Corals can also reflect the wavelength directly, but nearly none of us can see them with the visible range usually around 400-700nm - a few might be able to see lower than 400nm.

Most just look at protein excitement when discussing light wavelengths, but there is more to it than that.

Light from about 350-850nm has a use.

 

[taricha]

Just a comment on the green glowy water. This is indicating high organics, and if you filled a white bucket, you could probably detect some yellow to the water. Organics that can accumulate in saltwater fluoresce a little blue-green in response to near UV light.
You can remove a lot of this stuff with some GAC.

 

[Lobophyton]

Just a comment on the green glowy water. This is indicating high organics, and if you filled a white bucket, you could probably detect some yellow to the water. Organics that can accumulate in saltwater fluoresce a little blue-green in response to near UV light.
You can remove a lot of this stuff with some GAC.

Thanks, that's why my white light make the tank looking yellow