extra feeding can cause coral browning??

[redadeath]

usually some of my corals not all speciall the green or yellow of them not the red or orange
went brown after a period of time

does algae scrubber cause that??
aslo most of my coralin algae is green

my parameters are good
tank is 132 gallon with sump system
chaeto refugim + mature algae scrubber + sulphur denitrator

my parameters
are
zero phos + nitrates
light2x mh 250 watt hamilton technology
mag 1380
kh 10
calcium 420
temp 26 celcius
ph 8.3 8.4

i wonder something is not ok in my water that makes coral to brown

it makes me feels leaving the hobby

i want to know what actually make it brown

i dont think it is light issue
cause i tried to move galexia spp to different places and when i move it up it seems to get darker tint

i know it may be not the write place for this thread but i guess it related to water chemistry in some issue

can some expert help please

[HighlandReefer]

Light intensity and wavelength can cause coral to brown out. The 10,000 K light wavelength browned some of my corals and then changed to 20,000 K where they greened up. Depth in the water column can be a big factor. Also raising your lights if possible can help out as well.

Extra feeding can cause coral to increase the number of their zooanthaellae which may appear browner in color. This is relative to the total dissolved organic chemicals which feeding contributes to. Unfortunately, we have no hobby grade test kits to determine the total dissolved organic chemical levels. Running GAC may help reduce the dissolved organics and perhaps changing it out more often or cutting back on the total amount you feed.

It can take time for coral to adapt once you make changes to lighting and feeding. Perhaps even 30 days or more. So you want to go slow when making changes and perhaps just change one parameter at a time. ;)

[IamLoki]

Light intensity and wavelength can cause coral to brown out. The 10,000 K light wavelength browned some of my corals and then changed to 20,000 K where they greened up. Depth in the water column can be a big factor.

Just to add my experience: I got a ORA Hawkins frag a month or so ago that was bright blue-green. I was acclimating it in the sandbed and forgot about it until I noticed it was browning out. It stayed in the sandbed for 3 weeks. I've moved it up about half way and now it's starting to color back up. I believe that browing is due to insufficient light where as bleaching is due to too much light.

[tmz]

Nutrients and/or light can cause browning and/or bleaching ,imo.

Zooxanthelae are brown. They produce oxygen and the sugars the coral needs and use C02 water and light to do so. They also produce oxygen.

When zooxanthelae are highly active as in high light they put out more oxygen than the coral can handle ;so, some are expelled as the coral tries to regulate harmful oxygen radicals. Color is affected by light as the coral sheds brown zooxathelae when more light is avaialbe and develops protective pigments which affect color too. The overactive , overplentiful zooxanthelae can lead to bleaching as the coral may expell too many or become photinhibited or are harmed by the oxygen radicals.

Excess nutrients, organics, nitrates can produce browning as they fuel more brown zoxanthelae. Bleaching can also occur as oxygen radicals increase .Some of the excess zooxanthelae may compete for carbonate with the coral.

Low light can make the coral produce more zooxanthelae and brown it. But ifi t's too low it can also lead to bleaching.

Stress from infection , a predator or parasite, a wound or sting ,trouble in calcification brought on by high PO4 may also lead to browning and/or bleaching.

Zooxantelae can use nutrients including organics and inorganic nitrogen like nitrate . When in excess more zooxanthelae grow than are needed leading to similar issues with browning.

[redadeath]

what if all paramters are good zero nitrates and phosphate

can algae scrubber brown corals??

[tmz]

I don't think an algae scrubber would cause browning so. The algae will add some organics from exudate but I don't see how that would be a signifiant factor in browning. Perhaps if the algae is dieing from a PO4 limitation or nitrogen defficiecy it could be an issue.. How do you keep it alive with 0 PO4 and 0 nitrate. The chaeto I use starts to die off when PO4 is that low. What ae you using to test PO4 and NO3? Is your sulfur denitrator producing Hydrogen sulfide , sewer gas odor?

[redadeath]

What ae you using to test PO4 and NO3
phosphat i use sera and jbl
they are undetected

and nitrates i use sera test it is also undetected
i have seen people have succesful sps tanks with nitrates over 10 mg !!!!!!!!!!!1
Is your sulfur denitrator producing Hydrogen sulfide , sewer gas odor?
no
i dont make it drips it is very weak flow
and no odors at all


i just feed the tank 4 or 5 days at night with blender mesh (seafood + nori + amino acids+spirulina+phyto)

[IamLoki]

So, what is the K rating of your lights and what type of corals are browning out?

[tmz]

I agree 10 ppm nitrate won't likely cause browning either and yours is lower than that.
Sounds like lighting is moving up the list of suspects( what is it btw) assuming you re confident in your tests for nutrients ? Is your algae in the scrubber or fuge dying? Any chance of metals like fee copper in the system?

[redadeath]

So, what is the K rating of your lights and what type of corals are browning out?
hamitlon technology 14000 kelvin 250w* 2 tank is 60 cm deep and bulbs over the surface by 30 cm
the galexia spp. is browning

I agree 10 ppm nitrate won't likely cause browning either and yours is lower than that.
Sounds like lighting is moving up the list of suspects( what is it btw) assuming you re confident in your tests for nutrients ? Is your algae in the scrubber or fuge dying? Any chance of metals like fee copper in the system?

no algae is very good and i scrubb whole green screen weekly
my temp. was 31-32 degrees celcius when i added galaxeia.spp
and now it is 26 celcius

do u think temprature doing that

i dont think i have any source of copper in my tank
also the scrubber will absorb it in case it exists

[tmz]

I use those lights about 22 cm off the water of a 24 inch (ca 60 cm ) tank. I also use vho actinics with them. What you have sounds fine. The vhos do get colors I like though.

An algae scrubber won't remove free copper, Cu which is the toxic type . It can be lethal in small amounts in parts per billion. Algae like any other organism will take up some amounts of bound copper. Personally, I wouldn't count on algae to prevent metal toxicity which might otherwise occur. Doesn't sound like metal toxicity is your problem in any case.

32 C/89.6 F is hot and likely will likely do damage. High temps accelerate metabolism . Zooxanthelae growth accelerates along with other biological processes in the tank to a point where the zooxanthelae becomes pathogenic to the coral rather than symbiotic leadingto browning and or bleaching.

[tmz]

I use those lights about 22 cm off the water of a 24 inch (ca 60 cm ) tank. I also use vho actinics with them. What you have sounds fine. The vhos do get colors I like though.

An algae scrubber won't remove free copper, Cu which is the toxic type . It can be lethal in small amounts in parts per billion. Algae like any other organism will take up some amounts of bound copper. Personally, I wouldn't count on algae to prevent metal toxicity which might otherwise occur. Doesn't sound like metal toxicity is your problem in any case.

32 C/89.6 F is hot and likely will likely do damage. High temps accelerate metabolism . Zooxanthelae growth accelerates along with other biological processes in the tank to a point where the zooxanthelae becomes pathogenic to the coral rather than symbiotic leadingto browning and or bleaching.

[IamLoki]

I've seen brown varieties of that coral. Was it green when you got it? Do you spot feed it? Is that the only coral browning? Sounds like you have everything in check.

http://animal-world.com/Aquarium-Coral-Reefs/Galaxy-Coral

An excerpt from the link:

Galaxea corals comes in are green, red, brown, gray, and pink, as well as mixtures of these. The outer tentacles extending from each corallite tend to be clear or translucent, becoming more opaque toward the center. They are often tipped in white, or sometimes a lighter variation of their colors. The polyps range in size, up to 6mm in diameter, and tentacles are often extended during the day. Long sweeper tentacles, up to 12" (30 cm), come out at night.

The Galaxy Coral likes a low to moderate water flow and medium to bright light. Don't house them in a crowded aquarium with many other corals unless you can provide 12 inches or more between the Galaxea genus and other sessile invertebrates. Care must be taken in regards to its placement in the tank and the water flow around it as the sweeper tentacles, which will stretch in strong currents. These tentacles have a strong sting and it can do great harm to other corals within its reach.

[redadeath]

What ae you using to test PO4 and NO3? Is your sulfur denitrator producing Hydrogen sulfide , sewer gas odor
i dont use vho as supplemental ligh
just regular actinic 40 watt bulb .. that what i can find in market ... should i add another actinics

i cheched the denitrator and it was very dirty and the aragonite chamber too... the smell was bad but very faint sewer smell

i washed both of them with fresh water .... i depend on it in mainaining my nitrates at zero inspite i am not making it dripping but full weak flow

do u think that's the problem??

[IamLoki]

32 C/89.6 F is hot and likely will likely do damage. High temps accelerate metabolism . Zooxanthelae growth accelerates along with other biological processes in the tank to a point where the zooxanthelae becomes pathogenic to the coral rather than symbiotic leadingto browning and or bleaching.

Yes, I agree that is a bit warm and may be the source of the browning.

[redadeath]

Was it green when you got it? Do you spot feed it? Is that the only coral browning?

yes it was green

yes i spot feeding

no i got another mushroom browning and when i changed the flow and raised it alittle bit it seems to be getting it's colour