Browning corals

GoJimmy · Oct 14, 2016

Hi reefers.
I have been noticing lately that some of my sps corals have been browning. Months ago, I was dealing with a tank that was an ulns, and gradually over the past couple of months I have really stabilized the water parameters.
Cal 450
Alk 9
Mag 1350
NO3. 2
PO4. 0.02
pH 8.1

I dose with acropower, marine snow, and coral frenzy.

I have kept these parameters stable for over 2 months.
I'm using a evergrow 2040 led light and ramping my timer to a max of 50%blue and 50% white at peak and then down again
I have ordered and I'm waiting on a replacement upgrade board from sbreef lights

Am I experiencing some browning because my lighting is too low? Should I start gradually increasing my lighting.

mcarroll · Oct 14, 2016

I'd cut back on the particles OR the dissolved nutrients....corals should use up more dissolved nutrients if they aren't eating "the old fashioned way". And vis versa...they will have little to no requirement for dissolved nutrients if they're getting adequate nutrition from the particles.

GoJimmy · Oct 14, 2016

mcarroll said:
I'd cut back on the particles OR the dissolved nutrients....corals should use up more dissolved nutrients if they aren't eating "the old fashioned way". And vis versa...they will have little to no requirement for dissolved nutrients if they're getting adequate nutrition from the particles.

I really don't dose that much. Once a week. I feed the fish daily with flake food and every other day with a frozen cube

reeferfoxx · Oct 14, 2016

Cut back on flake food. It's much higher in nutrients than frozen.

mcarroll · Oct 14, 2016

I would just stop then...let the corals feed on what remains. (Which they will!

)

Excess dissolved nutrients are likely to do nothing more than cause the symbionts to multiply in number – often causing browning.

Lighting
Sorry I completely missed the lighting angle on the original post.

Get a lux meter app for your smart phone and take a reading at the water surface. For starters, see what you get for a peak reading and what you get around the perimeter of the tank.

I'd also recommend picking up a handheld lux meter like the "LX-1010B" that i use....should be less than $15, delivered. Better readings than the phone's light sensor and safer to use around your tank!

Let us know what you get for light readings!!!

GoJimmy · Oct 14, 2016

mcarroll said:
I would just stop then...let the corals feed on what remains. (Which they will! )

Excess dissolved nutrients are likely to do nothing more than cause the symbionts to multiply in number – often causing browning.

Lighting
Sorry I completely missed the lighting angle on the original post.

Get a lux meter app for your smart phone and take a reading at the water surface. For starters, see what you get for a peak reading and what you get around the perimeter of the tank.

I'd also recommend picking up a handheld lux meter like the "LX-1010B" that i use....should be less than $15, delivered. Better readings than the phone's light sensor and safer to use around your tank!

Let us know what you get for light readings!!!

Looks like around 15500lux in the center of the light and approx 5500lux around the perimeter.

The only reason I dose is due to the original point that I started with an ulns and very pale corals . NO3 was 0, PO4 was 0 and everything was bleaching. Once I started to dose some nitrates and feed more, my corals colored nicely. Now some are browning and I wondered if it was the lights. I don't feed that much , just daily and not a lot. I feed enough to keep my No3 and Po4 stable at 2 and 0.02 for months. I know at my lfs, their water tested for much higher No3 but they keep their corals under metal halides or radions. Much brighter than I do.

mcarroll · Oct 14, 2016

Light
At those lux levels, you're definitely on the low end of the spectrum....increasing wouldn't be 100% necessary in my experience, but it could help in your case. If you can slowly raise it to around 25,000 lux on average, I think you might see some improvements. I don't think I'd raise it more than 2500 lux ever few weeks though....obviously observe and use your own judgement along the way.

Unless you had a light meter with you at the store (which I highly recommend!!!!) it's painfully hard to judge by eye if their lights are really brighter. Ambient lighting even plays significantly into perceptions like this. A meter isn't perfect either, but it's much much more objective.

Food
I'm with @reeferfoxx on the flake food. I think I'd file-13 the flake and liquid food/supplments.

Refocus all feeding efforts on one or two high quality fish foods.

If, for one of the two, you can work a live food (like blackworms) into your routine, that is the best. There are many live food options – even ones that can be DIY'd.

Next best is frozen-whole foods.....one of which you're already feeding.

It has to be non-irradiated for maximum benefit. Not sure if commercial foods will be labelled on this front.

Feed flakes if you need to boost PO4...they really aren't so bad for the fish in the scheme of a diet like that above.

mcarroll · Oct 14, 2016

GoJimmy said:
Once I started to dose some nitrates and feed more, my corals colored nicely.

This is an indication that I think I'd lay completely off the particle foods for corals...stay with dissolved.

But whichever you pick (I'm not sure which to say is "better") I would pick one and stop feeding corals both particulate food as well as dissolved.

2¢

GoJimmy · Oct 15, 2016

mcarroll said:
This is an indication that I think I'd lay completely off the particle foods for corals...stay with dissolved.

But whichever you pick (I'm not sure which to say is "better") I would pick one and stop feeding corals both particulate food as well as dissolved.

2¢

Can you explain what you mean by particulate food vs dissolved? I thought overfeeding would result in elavated nitrates and phosphates. Mine are stable and at resonable levels. I'm not sure that it is excess nutrients that are causing the browning. On a 29gal cube, I'll dose 1cap acropower once per week, and 1 cap marine snow and 1/8 teaspoon frenzy every other week. Water changes are done weekly, 4gal/wk.
I still believe that my lighting could increase. I will try slowly increasing my lighting, particularly the blue channel over the next few weeks/months to 75% during the mid day peak and keeping the whites at 50%

mcarroll · Oct 15, 2016

Dissolved are things like nitrate, ammonium, urea, phosphates, etc. You can even include gasses like nitrogen, co2, etc if you want.

Particles are things like fish food, fish poop, detritus, zooplankton, phytoplankton, etc.

Corals are natively predators. Maybe due to this, it seems that if they are able to feed this way (off of particles) they do not translocate nutrients with their symbionts as much, or at least in some cases, at all. Within a few days of cessation of feeding, they will begin translocating nutrients from/to their symbionts as usual again.

Their symbionts will utilize dissolved nutrients before translocating them to their host, and multiplying in number (darkening the colony) is one of their first responses. Photosynthetic corals found growing very very deep have been described as being almost black on the side facing the surface.

I think that sounds like a great plan for the lights.

reefwiser · Oct 15, 2016

Zooxanthellae are normally a brown color. When you have an over population of zooxanthellae and seeing the coral turn brown this is the problem.
http://ocean.si.edu/slideshow/zooxanthellae-and-coral-bleaching
http://reefworks.co.uk/articles/obtaining-the-best-colours-from-your-corals/

GoJimmy · Oct 15, 2016

mcarroll said:
Dissolved are things like nitrate, ammonium, urea, phosphates, etc. You can even include gasses like nitrogen, co2, etc if you want.

Particles are things like fish food, fish poop, detritus, zooplankton, phytoplankton, etc.

Corals are natively predators. Maybe due to this, it seems that if they are able to feed this way (off of particles) they do not translocate nutrients with their symbionts as much, or at least in some cases, at all. Within a few days of cessation of feeding, they will begin translocating nutrients from/to their symbionts as usual again.

Their symbionts will utilize dissolved nutrients before translocating them to their host, and multiplying in number (darkening the colony) is one of their first responses. Photosynthetic corals found growing very very deep have been described as being almost black on the side facing the surface.

I think that sounds like a great plan for the lights.

Thanks for all you help!

reefwiser · Oct 15, 2016

Forgot to add that what systems like Aquaforest and ZEovit do is get corals to expel zooxanthellae with additives and the keeping of the phosphates and nitrate low which is called a UNLS.
https://www.reef2reef.com/threads/ultra-low-nutrient-systems.160187/

bubbaque · Oct 15, 2016

I see most people saying that a brown coral is usually caused by low light or high nutrients. In one of the articles it says a coral will turn brown if there are not enough nutrients. The coral will produce more zooxantelle to make up for lack of nutrients. "There is another aspect to this process as well. On coral reefs there is a huge abundance of zooplankton and phytoplankton that a coral can capture and and utilize as an energy source. If this coral is placed in an aquarium where the levels of prey abundance are much lower then the coral needs to get it’s nutrition from elsewhere, as a result the coral increases the numbers of zooxanthellae that it holds in it’s tissues, regains it’s nutritional requirements and has turned brown."

scardall · Oct 15, 2016

@GoJimmy I would switch from acropower to ME polyp extender. You will have better results with ME. I also had used acropower. Increase lighting in stages .

GoJimmy · Oct 15, 2016

scardall said:
@GoJimmy I would switch from acropower to ME polyp extender. You will have better results with ME. I also had used acropower. Increase lighting in stages .

I tried looking for ME polyp extender but I don't think it's available in Canada