What's making my corals turn brown?

[Kongar]

Hi all,

Wondering if you can guide me with respect to corals browning out. Most, but not all, of my corals are losing their colors and turning/ed brown. All the SPS frags (relatively new tank btw - 1yr old), have turned solid brown and lost all color. They aren't growing fast / at all. My LPS are changing colors - for example, my torch has lost all the yellow, and is now brown with it's blue tips. My rainbow colored acans are now just red and blue. One of my chalices has lost all it's rainbow colors and turned purplely brown. Some corals look as good as they ever did, an elegance, a frogspawn, two other chalices, and a monti cap. These, along with coraline algae, are growing like weeds.

I know this can be:

1. High nutrients
2. Not enough light
3. instability

I'm leaning towards instability as I've been battling dinos for quite some time now. I just went through round two of that fight - not as bad as the first, but still kicked my corals in the pants. I used DinoX both times as I've been really unsuccessful with the other methods. But, the color changes happened before the first round of dinos, and also inbetween. I guess I'm trying to figure out if I should just leave things alone, start raising the light intensity, or try for lower nutrients. I'm thinking I should just "be stable" and try that for a while and see if they color up. Also wondering how long to see results (6mo?). Interested in your thoughts and advice - thanks!

Nitrate - It's usually around 2ppm, but it's swung from 0-10 during fighting dinos
Phosphate - it's usually around 0.05, but it's swung from 0.03 to over 0.1 during the dino fight
ammonia and nitrites - undetectable since the cycle a year ago
Salinity is always at 35ppt
Mg - Always pretty stable at 1480
Ca - Always pretty stable at 460

I feed pellets once a day, sometimes I feed mysis.
Once a week, I spot feed my corals reef roids
I dose a small amount of phyto every day (not sure it does anything, but I've been doing it, and I'm afraid to make changes and have another dino outbreak)

I've measured my par with a seneye, my LPS get about 150PAR, and my SPS get about 225, give or take. It's a nano tank, so it's hard to crank up the lights for the sps and not overpower the lps. But I think I could go higher if I went slowly and not harm the lps.

Thanks for the help, been reading a lot and a little torn on what to do, if anything at all.

 

[ZoWhat]

Corals turning brown is when the corals loses its zooxanthellae algae color within its tissues.

Id do a deep dive research on the keyword: zooxanthellae

 

[Stuartmercer]

Corals turning brown is when the corals loses its zooxanthellae algae color within its tissues.

Id do a deep dive research on the keyword: zooxanthellae

It's actually when the coral increases the population of zooxanthellae in it's tissue. With that said, yes it could be all large number of things like posted above. It could be the instability, lighting, nutrients, etc, but it's difficult to pin point exactly which one if there are multiple issues going on. Hopefully others will chime in.

 

[Rollman]

SPS are sometimes unforgiving and you potentially have a few issues out of whack. If your worried about SPS I’d raise nutrients and salinity gradually first. Hope it worked out.

 

[Adrianna]

Can the coral colors come back after the browning? I'm having the same issues

 

[Pistondog]

Can the coral colors come back after the browning? I'm having the same issues

Yes, increase light. Takes a few weeks

 

[jmichaelh7]

whats your phosphate and nitrate params

 

[Ghost25]

My first guess would be light, how blue is it? Whiter light tends to cause corals to go brown, bluer light makes them color up more. I wouldn't be as worried about hitting them with too much light, many corals can take more than you think.

 

[JCM]

My first guess would be light, how blue is it? Whiter light tends to cause corals to go brown, bluer light makes them color up more. I wouldn't be as worried about hitting them with too much light, many corals can take more than you think.

No it doesn't. They won't fluoresce like a black light poster but they won't turn brown.

 

[blasterman]

White light from a reef light and blue light have nearly the same PAR per watt. Blue is the main component of artificial white light sources used on reef tanks.

 

[Kongar]

So all my corals except one have started coloring back up. I’ve increased my lighting intensity about 10% and kept my parameters stable (albeit a little high). ~8 nitrates and .14 phosphates. Corals look better than ever. Just posted a video of you want to go hunt down my build thread.
Bottom line: yes they can recover from being brown.

 

[Ghost25]

No it doesn't. They won't fluoresce like a black light poster but they won't turn brown.

Ok what are you basing that on? If you have a tank that runs really red/white light and has colorful coral I'd like to see it. To be clear, brown doesn't necessarily mean unhealthy. Corals in the wild are often quite brown. Here are some in shallow water, all very happy and very brown.

White light from a reef light and blue light have nearly the same PAR per watt. Blue is the main component of artificial white light sources used on reef tanks.

PAR is a useful measure but spectrum is at least as important if not more so. You could have monochromatic blue light and monochromatic red light with equivalent PAR but corals will react very differently to those and both will be different to a metal halide with the same PAR.

Yeah there's blue in white light but there's a lot of longer wavelengths too. There's a reason most people's tanks are not lit with warm white.

 

[ajm83]

Ok what are you basing that on? If you have a tank that runs really red/white light and has colorful coral I'd like to see it. To be clear, brown doesn't necessarily mean unhealthy. Corals in the wild are often quite brown. Here are some in shallow water, all very happy and very brown.

PAR is a useful measure but spectrum is at least as important if not more so. You could have monochromatic blue light and monochromatic red light with equivalent PAR but corals will react very differently to those and both will be different to a metal halide with the same PAR.

Yeah there's blue in white light but there's a lot of longer wavelengths too. There's a reason most people's tanks are not lit with warm white.

Yeah but you've gone from saying 'bluer vs whiter' to quite an extreme example of 'really red/white light'

I had to move my tank to my mum's place because my house needed structural repairs. The blue light annoyed her, so i gradually added more cool white until it was tolerable. The change was something like from 10 to 80% cool whites (AI Hydra 26HDs).

I was surprised that it seemed to make the acros skin start to change colour. Not florescent but like a tint.

And you could see the colour in sunlight, whereas when they had been lit under blues, all there was was the florescent colours and they looked a drab tan colour in sunlight. ‍

 

[Ghost25]

Yeah but you've gone from saying 'bluer vs whiter' to quite an extreme example of 'really red/white light'

I had to move my tank to my mum's place because my house needed structural repairs. The blue light annoyed her, so i gradually added more cool white until it was tolerable. The change was something like from 10 to 80% cool whites (AI Hydra 26HDs).

I was surprised that it seemed to make the acros skin start to change colour. Not florescent but like a tint.

And you could see the colour in sunlight, whereas when they had been lit under blues, all there was was the florescent colours and they looked a drab tan colour in sunlight. ‍

So your colors actually got better when you went from 10% white to 80%? That's interesting, do you have before and after pics?

 

[ajm83]

So your colors actually got better when you went from 10% white to 80%? That's interesting, do you have before and after pics?

I wouldn't say better as such. Under blues they looked the same to my eyes.

They seemed to gain colours that only showed under whites.

I remember hearing Dana Riddle talking on YouTube some years back about non-florescent colour proteins, my assumption was that the coral was expressing those to protect themselves from the white light (where as the florescent proteins are to protect it from blue light - might be completely wrong though!!)

Also I was thinking after posting yesterday and actually can't guarantee it wasn't just from the increase in PAR (or some other change).