redadeath
New member
i know it is not the proper place for this thread
but i think zooxanthella can be overpopulated by excess light
as i read about farmers do that to incrase growth by placing aquacultured corals at the surface of the water to increase it's growth rate
and so it turns brown
see this thread
Quote:
I have an aquarium business and I have purchased farm raised corals and imported maricultured and wild corals. Here is what I've learned:
- Most all sps will loose at least some of their color if not turn brown during shipping. I think this is probably caused by stress.
- Farm raised will acclimate faster and their color will return faster than any others.
- Some maricultured or wild corals can take months to acclimate and some may never color back up. But, some may be more colorful than in the wild. I don't know of a way to pick the right ones. I think it's the luck of the draw. I have had wild corals take 6 months before I ever saw polyp extension.
- Lighting (READ THIS IF NOTHING ELSE): Quantity of light is important but quality (spectrum) is more important. It is possible to have too much light and cause corals to brown out. Here's why: We all know about the Zooxanthellae algae that grows symbiotically in corals and we all know that they use light for photosynthesis and we all know that light stimulates their growth. But contrary to popular belief the Zooxanthellae does not give the coral its color, they are BROWN. Protiens within the corals tissue react to certain SPECTRUMS of light, either absorbing or reflecting. I'm sure we've all noticed how our coral look with and without the actinics on under different spectrums. What you are seeing is color absorbtion or reflection.
Know we know that the Zooxanthellae is brown, which obviously give the corals a brown color. First, if your lighting is too low, your coral will do whatever it can to get more light to the Zooxanthellae, which is for it to basically to have a dark drab color to absorb light. Also, TOO MUCH light will cause the Zooxanthellae to grow out of control and dominate the coral color and cause it to look brown. Consequently, this will also cause the corals to grow faster but they won't be colorful. This is a trick that coral farmers use. They will put corals in high light to get them to grow fast, but they are brown. They then move them to PROPER lighting and color them up to sell.
So, What I've found out through reading, research and my experience is that most SPS corals will thrive and have the brightest colors with a light spectrum of 14,000K to 15,000K. Wild and mariculture corals will color up faster under T5HO lighting than Metal Halide, which I've read is because of the even light spread of T5's. I don't know why for sure, but I know it works.
Acclimation - On a side note, this is something I didn't know but got the info from a coral farmer and is how I acclimate corals now:
Drip acclimating corals can kill them. Corals will arrive with a certain amount of die off in the bag and drip acclimation can cause an ammonia spike and kill them.
To properly acclimate, float the bag for 15 minutes until temperature equals tank water and quarantine or put them in your tank (which ever method you practice). Corals need to be temperature acclimated only, anything else is a waste of time and money and could possibly damage the coral.
I know this is against popular belief, but I figured a coral farmer knew what he was talking about. I have since only temperature acclimated corals and have never had a loss from it.
http://www.reefcentral.com/forums/ne...ewthread&f=112
the problem is i have stable parameters and stable kh and undetectable po4 and no3 for more than year now
and i have wild acropora for 3 month and they still brown
they tend to colour up at the tips but still have green dark zooxanthella
i place them very high only 2o cm from the top of the water
i have 400* MH radiums that place 25 cm above the tank
so can extra uv or light cause increasing in zoxxanthella that can make corals brown ???
thnx for help
but i think zooxanthella can be overpopulated by excess light
as i read about farmers do that to incrase growth by placing aquacultured corals at the surface of the water to increase it's growth rate
and so it turns brown
see this thread
Quote:
I have an aquarium business and I have purchased farm raised corals and imported maricultured and wild corals. Here is what I've learned:
- Most all sps will loose at least some of their color if not turn brown during shipping. I think this is probably caused by stress.
- Farm raised will acclimate faster and their color will return faster than any others.
- Some maricultured or wild corals can take months to acclimate and some may never color back up. But, some may be more colorful than in the wild. I don't know of a way to pick the right ones. I think it's the luck of the draw. I have had wild corals take 6 months before I ever saw polyp extension.
- Lighting (READ THIS IF NOTHING ELSE): Quantity of light is important but quality (spectrum) is more important. It is possible to have too much light and cause corals to brown out. Here's why: We all know about the Zooxanthellae algae that grows symbiotically in corals and we all know that they use light for photosynthesis and we all know that light stimulates their growth. But contrary to popular belief the Zooxanthellae does not give the coral its color, they are BROWN. Protiens within the corals tissue react to certain SPECTRUMS of light, either absorbing or reflecting. I'm sure we've all noticed how our coral look with and without the actinics on under different spectrums. What you are seeing is color absorbtion or reflection.
Know we know that the Zooxanthellae is brown, which obviously give the corals a brown color. First, if your lighting is too low, your coral will do whatever it can to get more light to the Zooxanthellae, which is for it to basically to have a dark drab color to absorb light. Also, TOO MUCH light will cause the Zooxanthellae to grow out of control and dominate the coral color and cause it to look brown. Consequently, this will also cause the corals to grow faster but they won't be colorful. This is a trick that coral farmers use. They will put corals in high light to get them to grow fast, but they are brown. They then move them to PROPER lighting and color them up to sell.
So, What I've found out through reading, research and my experience is that most SPS corals will thrive and have the brightest colors with a light spectrum of 14,000K to 15,000K. Wild and mariculture corals will color up faster under T5HO lighting than Metal Halide, which I've read is because of the even light spread of T5's. I don't know why for sure, but I know it works.
Acclimation - On a side note, this is something I didn't know but got the info from a coral farmer and is how I acclimate corals now:
Drip acclimating corals can kill them. Corals will arrive with a certain amount of die off in the bag and drip acclimation can cause an ammonia spike and kill them.
To properly acclimate, float the bag for 15 minutes until temperature equals tank water and quarantine or put them in your tank (which ever method you practice). Corals need to be temperature acclimated only, anything else is a waste of time and money and could possibly damage the coral.
I know this is against popular belief, but I figured a coral farmer knew what he was talking about. I have since only temperature acclimated corals and have never had a loss from it.
http://www.reefcentral.com/forums/ne...ewthread&f=112
the problem is i have stable parameters and stable kh and undetectable po4 and no3 for more than year now
and i have wild acropora for 3 month and they still brown
they tend to colour up at the tips but still have green dark zooxanthella
i place them very high only 2o cm from the top of the water
i have 400* MH radiums that place 25 cm above the tank
so can extra uv or light cause increasing in zoxxanthella that can make corals brown ???
thnx for help
