What effect do waves have on the absorption of light by corals

[Lloyd]

Many people are looking at water movement as an important and sometimes neglected part of reefkeeping. What data do we have for ideal flow levels in our tanks and just as important , how do we provide this flow? How do surface waves affect light, we all see glitter lines from metal halides, do they alter the way the corals photosynthesize , do they offer bursts of energy that can be used, by altering the surface movement can we in some way regulate the type and strength of these bursts of energy hitting the zoo?
High water circulation rates may affect more things too, what about growth rates , detritus settlement, growth shapes, fish health and coral reproductive conditioning.
When do high water movement rates become too much? we can visibly see soft corals struggling with too much flow, but what about acropora and their ilk? Are there signs that sps corals are receiving the correct amount of flow such as polyp extension . Maybe the old addage of X times water flow is insufficient, should we be looking at new methods to determine what is neccessary. I would love to see ideal water flow speed requirements become more important in explianing what our corals need, then we can all buy a new gadgets for measuremnet or make our own home made devices .
My 45 gall tank has now 6 1200 lph powerheads on a wave maker and it still doesnt seem enough, every time i add another, things look better. Anyone ever tried something like tunze streams in a little tank? Now i am reaching the stage where my DSB is going so I can increase the flow further, my next tank will not have a DSB and one of the resaons is to turn it into a blender, ahh i can see it now , the starboard blender........

[Lloyd]

I'll get my coat.....

[thefatman]

^^^^^

[Spanky]

As soon as I stop laughing, I'll think of something.
Keep your coat on Lloyd
In the mean time, you mean to tell me no one has any idea on this??

[mojoreef]

Lloyd its more of what the flow rate and the motion does for the corals in your tank. Flow in the wild brings food, takes away detritus and keeps thier surfaces clean (thus keeping infections away). In our tanks flow can be used for the same as above plus a couple of little extras. I guess its all individual wants so I will discribe mine.
The main reason I used high ammounts of flow is to keep the detritus suspended in the water column. This makes the detritus available to those that eat in and takes it out of the main tank and makes it available to the skimmer, where it is removed. In addition to this I created 4 sections of the tank that each get huge surges of flow followed by short periods of slack flow (about 7 minutes each way). The chaotic flow recreates wave action pounding in on the reef and then the slack flow creates the slow draw of the wave back out.

Mike

[gregt]

Originally posted by Spanky
As soon as I stop laughing, I'll think of something.
Keep your coat on Lloyd
In the mean time, you mean to tell me no one has any idea on this??

Ok, let me reach around and pull something out of my butt to give spanks time to collect his thoughts.

I can't really comment from the perpective of how a coral uses the light, or how the variety of light the waves cause effects the coral, but I can comment from an observers point of view and apply some common sense....IMO:

Waves, in general, cause a reduction in the available light. On the other hand, they also increase the amount of light by refracting and focusing intense light on a given spot, however, I've always felt that usable light at typical reef depths is not nearly as high as we are led to believe.

During the millisecond that the wave focuses intense light on the coral, do they really have time to use that intense light? I don't know, but I suspect not. I suspect the lion's share of usable light is the "average" much lesser intense light that is given to the coral on a more consistent basis.

So, it's my opinion, with no facts really to back it up, that wave action decreases available light and may in fact be the cause for some of what I consider miscalculation of how much light our tanks need.

However, with that said, I think that if you keep your tank surface more "turbulent", you do need more light to overcome the loss of efficiency in getting the light through the waves.

Ok, spanky, tell me why I'm wrong.

[galleon]

During the millisecond that the wave focuses intense light on the coral, do they really have time to use that intense light?

Yes, thats all it takes to excite an electron into photophosphorylation.

I suspect the lion's share of usable light is the "average" much lesser intense light that is given to the coral on a more consistent basis.

Agreed. This is the most reliable source.

[mojoreef]

Why would Light waves become less intence if passing through surface aggitation?? (such as a wave). Deflected elsewhere yes but how does it loss its intencity???

MIke

[gregt]

Originally posted by mojoreef
Why would Light waves become less intence if passing through surface aggitation?? (such as a wave). Deflected elsewhere yes but how does it loss its intencity???

MIke

The intensity at the point where it strikes the coral is less. The "lost" intensity is distributed as reflection back out of the water and at greater angles which cause more loss by having to travel a greater distance through the water to strike the coral (and potentially be reflected by flotsam and other "junk" in the water).

[Mkelly]

Originally posted by mojoreef
Why would Light waves become less intence if passing through surface aggitation?? (such as a wave). Deflected elsewhere yes but how does it loss its intencity???

MIke

Actually I don't think it does. If anything the refraction intensifies it. Lemme hit the books on this one

Yay! something else to read!!

[Spanky]

Glitter Lines

but it takes sustained photophosphorylation for the process to go through to completion.

[mojoreef]

Greg I can understand the light being reflected out of the water due to the inclines of the rougher water. But if we are refering to say the home reef tank, I dont think it would pertain as much. Yes the angles would be greater for say one given point , but then again it could be less for another. Also it could generate light again to any given point in which it might not recieve light from that direction if the water was calm? If we look at a standard tank being between 24 and 30 inches deep, I think it would be safe to say if properly lite the intencity shifts caused by waves shouldnt have any real bad effects. One could even say with the lighting waves being deflected/detoured and in constant motion from the surface aggitation that it may be a better thing in giving the corals in our tank more lighting form more different angles??
In regard to them scum and doc's these for sure will lessen the intencity and keep light away from the corals.


Mike

[mojoreef]

but it takes sustained photophosphorylation for the process to go through to completion

Its not like it goes dark when the surface is bending the light waves

[galleon]

Glitter Lines

but it takes sustained photophosphorylation for the process to go through to completion.

Is there an echo?


Everything absorbs light energy at certain wavelengths in water, including the hydrogen bonds of the water itself (this is what makes water bluer with depth). The water's surface reflects light, the African dust in the atmosphere reflects and absorbs it before it gets there (But seriously, African dust is why coastal Florida sunsets are so red for the most part), the suspended particles reflect and absorb light... and on and on.

Refraction does not absorb or reflect light, it only bends it.

Glitter lines do not come from refraction only, they come from the shape of the surface of the water acting as a focusing lense (come on mojo, you know you used to cook ants with the hand lense).

[Spanky]

Mike would never do that!