lighting

[marinakid]

hi all reefers,

can someone enlighten regarding actinic light and 20 000k light? they both put out 'blue' light. can i say that they are the same actually? been surfing the whole afternoon but cant seem to find 1.

and also, does anyone use a air stone in their marine tank ?

[MOssrope]

hi all reefers,

can someone enlighten regarding actinic light and 20 000k light? they both put out 'blue' light. can i say that they are the same actually? been surfing the whole afternoon but cant seem to find 1.

and also, does anyone use a air stone in their marine tank ?

this is a story of nanometers and kelvin which is actually pretty deep if you look into it.

Nanometers(nm) is the wavelength of the light spectrum.

Kelvin(K) is the colour temperature of the light.

Actinic light usually peaks at 400-420 nanometers. Which is about 7500k.

The higher the K the more blue the light spectrum becomes.

At 20,000k the peak wavelength should be about 150nm. This brings out the strongest blue pigmentation in corals like SPS but also does not help with its growth. Do Note i am talking bout the peak wavelength not helping with the growth but the other wavelengths are still present.

The output of the light is one important factor too. E.g MH v.s NO(normal output T8)

So to put it short... you cant say it is the same but there is no real test that can justify manufacturers claims on these K and nm.

Its best you know the output and nm well enough from the different distributors if you wish to be precise. lol

Take the deep sea for example. i mean DEEP. The main light source is the sun and by the time the light hits the sea bay.. only the blue spectrum is left. Thus thats why all your tanks have those blue spectrum lights usually.

These are just a few simple examples please correct me if i am wrong.

And for your 2nd question.

Air stones are usually placed in air driven skimmers.

The last time i saw air stones in tanks was at some fish shop around plaza sing area which some bros here take great notice off.

Their visibly "alive"(swaying) corals are their artificial corals so i think it might not be a good idea to try.

When the beer lady fails her job or when tanks with strong air stones get nutrient laden, you get a good amount of cappucino! <--(is this the right spelling? drink so many years still dunno zz)

[marinakid]

hi mossrope,

great write up, so am i right to say that using a actinic light at which it at around 7500k. it do help with the coral growth in some way?common coral we buy doesnt come from that deep an ocean so kelvin they uses it around 6500k. so for a 20 000k light basically it just bring out the colour of the coral. more for a cosmetic effect.

i am thinking of have a conditioning tank. more for conditioning water before water change. what mean can be use for aerating the tank?

this is a story of nanometers and kelvin which is actually pretty deep if you look into it.

Nanometers(nm) is the wavelength of the light spectrum.

Kelvin(K) is the colour temperature of the light.

Actinic light usually peaks at 400-420 nanometers. Which is about 7500k.

The higher the K the more blue the light spectrum becomes.

At 20,000k the peak wavelength should be about 150nm. This brings out the strongest blue pigmentation in corals like SPS but also does not help with its growth. Do Note i am talking bout the peak wavelength not helping with the growth but the other wavelengths are still present.

The output of the light is one important factor too. E.g MH v.s NO(normal output T8)

So to put it short... you cant say it is the same but there is no real test that can justify manufacturers claims on these K and nm.

Its best you know the output and nm well enough from the different distributors if you wish to be precise. lol

Take the deep sea for example. i mean DEEP. The main light source is the sun and by the time the light hits the sea bay.. only the blue spectrum is left. Thus thats why all your tanks have those blue spectrum lights usually.

These are just a few simple examples please correct me if i am wrong.

And for your 2nd question.

Air stones are usually placed in air driven skimmers.

The last time i saw air stones in tanks was at some fish shop around plaza sing area which some bros here take great notice off.

Their visibly "alive"(swaying) corals are their artificial corals so i think it might not be a good idea to try.

When the beer lady fails her job or when tanks with strong air stones get nutrient laden, you get a good amount of cappucino! <--(is this the right spelling? drink so many years still dunno zz)

[MOssrope]

hi mossrope,

great write up, so am i right to say that using a actinic light at which it at around 7500k. it do help with the coral growth in some way?common coral we buy doesnt come from that deep an ocean so kelvin they uses it around 6500k. so for a 20 000k light basically it just bring out the colour of the coral. more for a cosmetic effect.

i am thinking of have a conditioning tank. more for conditioning water before water change. what mean can be use for aerating the tank?

it is best to go for nm peaks when choosing bulbs if you wish to be accurate. Some manufacturers 20000k still has a very strong white base, probably leading to people thinking Higher K = better output.

6500k bulbs covers a large spectrum of wavelengths which you can see on graphs given by distributors. But peaks are around 460nm which is ideal for plants and many corals.

As K in these bulbs increase lets say 7500k+ it doesnt cover a wide variety of spectrum like daylight bulbs and moves to more solely on the blue spectrum side.

I did mention the difference in output maybe say 6500k Mh light and 6500k T8 florescent. For T8 the wavelengths and spectrum are cut out pretty fast before it actually hit the base of your tank, but for MH the spectrum are pretty consistent even in a deep tank.

As i said 20000k bulbs peak does not help in growth but brings out the best colouration("glowing power") while if you are using a MH with intense power.. there are still other wavelengths present which are not at their peak.

Peak wavelength and output power are what i am trying to emphasize in order to answer your question.

Which is why manufacturers like ATI encourages mixture of different bulbs which has seen much success with our fellow reefers here.

My eyesight got a lot worse researching all these back then.. but I still can be wrong in certain areas, but its pretty much this way.

[marinakid]

is there a thumb of rule of determine how much light is suffient for a tank? like say 4watt/gallon for maybe coral like LPS? i understand that different type of light have different penertrating power.

it is best to go for nm peaks when choosing bulbs if you wish to be accurate. Some manufacturers 20000k still has a very strong white base, probably leading to people thinking Higher K = better output.

6500k bulbs covers a large spectrum of wavelengths which you can see on graphs given by distributors. But peaks are around 460nm which is ideal for plants and many corals.

As K in these bulbs increase lets say 7500k+ it doesnt cover a wide variety of spectrum like daylight bulbs and moves to more solely on the blue spectrum side.

I did mention the difference in output maybe say 6500k Mh light and 6500k T8 florescent. For T8 the wavelengths and spectrum are cut out pretty fast before it actually hit the base of your tank, but for MH the spectrum are pretty consistent even in a deep tank.

As i said 20000k bulbs peak does not help in growth but brings out the best colouration("glowing power") while if you are using a MH with intense power.. there are still other wavelengths present which are not at their peak.

Peak wavelength and output power are what i am trying to emphasize in order to answer your question.

Which is why manufacturers like ATI encourages mixture of different bulbs which has seen much success with our fellow reefers here.

My eyesight got a lot worse researching all these back then.. but I still can be wrong in certain areas, but its pretty much this way.

[comycus]

is there a thumb of rule of determine how much light is suffient for a tank? like say 4watt/gallon for maybe coral like LPS? i understand that different type of light have different penertrating power.

Throw away these thumb of rule notions be it lighting, or stocking etc. I can have a 90 gallon tank that is 36x24x24 in dimensions or 48x24x18. Both have same gallonage but the former tank will require greater light penetration due to its depth. 4watts for LED is vastly different from 4W of T5 lightings or T8 or metal halides. Think you get my drift.

It will be better to specify your tank dimensions, what you wanna keep (in which part of the tank) to determine how much light you need.

[marinakid]

i'm having a 2 by 1 by 1 ft tank. i'm very interested to keep clam. currently using 4 x T5. it is alway recommended to use a MH for clam but i had found out that there are people who are successful with t5 light too.

Throw away these thumb of rule notions be it lighting, or stocking etc. I can have a 90 gallon tank that is 36x24x24 in dimensions or 48x24x18. Both have same gallonage but the former tank will require greater light penetration due to its depth. 4watts for LED is vastly different from 4W of T5 lightings or T8 or metal halides. Think you get my drift.

It will be better to specify your tank dimensions, what you wanna keep (in which part of the tank) to determine how much light you need.

[marinakid]

i'm having a 2 by 1 by 1 ft tank. i'm very interested to keep clam. currently using 4 x T5. it is alway recommended to use a MH for clam but i had found out that there are people who are successful with t5 light too.

is it require to have a 6500k light for a reef tank? possible to have just 2 blue and 2 actinic?