Acro's browning

[Dr. Dee]

Question what makes acro's turn brown?

1. Lighting is 400 watts MH HQI

2. 40 gallon tank

3. good turn time and flow

4. ppt 1.024

5. salt I O

6. Calcium 450

7. Ph 8.3

8. alk 9

9. zero nitrates

10. phosphates zero

11. Temp 78.5

I'am buged-out now its interesting to find out whats up with these coarls:?:

 

[DonW]

How old are the bulbs? What kelvin and brand of bulbs. What are you concidering good flow? What test kits are you using?

Don

 

[kevinpo]

The most common reason for Acropora corals to turn brown is adjustment to changes in lighting intensity and/or spectrum. Coloration is not an indicator of coral health. It can take up to six months for a coral to color up and depending on your bulb/ballast combination and the placement of the coral it may never be the same color as it was when you first got it. Some will remain brown until they are moved to a different location or put under a different spectrum or intensity bulb.

Your parameters appear to be well within the range to keep Acropora healthy and growing. IME higher kelvin bulbs tend to produce slower growth while producing good color on average.

I have a 450 that I had 1500W of halide/actinic light on for 5 months. 80% of the Acropora had great color and growth but a few of the blue ones started to turn brown. They were frags of parent colonies I have that I know need very high light to stay bright blue. So I added another 1200W without any acclimation to the photo period. Well about 50% of the colorful corals turned brown or rather light tan/cream colored. The blue ones got their bright blue back. It has been another 60 days now and the other corals are just starting to get their color back. I estimate that it will be another 60-90 days before they return to their full color. In severe cases where the light intensity is increased too much the coral will lose all its tissue in a day.

A few years ago on my 557gal tank I let the halide bulbs go too long before changing (about 16 months). Then I put 5 new 400W bulbs of the same brand and added ozone, 80% of the acropora corals turned brown for 6 months because of the increase in light intensity due to the new bulbs and increase in water clarity.

These are just a couple of examples of how lighting changes affect Acropora corals.

Organic compounds in the water can have a large impact on how lighting penetrates the water column.

Paitence is the key when keeping Acropora corals IME, and try not to change too many things at once trying to achieve the color you seek

Regards,
Kevin
PS: Some Acropora corals will remain/are brown and others will not change color until the lighting spectrum is changed (but not on average).

 

[Dr. Dee]

Kevin thanks for the help! Just to let you know what i have thats browning
are two wild bansai blue, purple humillis full colony and millepora red. I had a few superman montipora's turn also and the rest are fine,yes theses are tonga wild select. Note no red bugs or flat worms and also the ligths are three months old. Ok one more thing i'am useing sorry hamilton 14k HQI dubble end.

 

[kevinpo]

You're welcome
Wild corals are notorious for turning brown for long periods of time as they adjust to captivity. Many color up nicely but often not to their original color.

Regards,
Kevin

 

[Jumpincactus]

Yep Kevin is right on best way to retain coral colors are to stick with tank raised frags. Wild caught as Kevin stated can brown out and some may never recover. Just one more reason to conserve the reefs and stick with hobbyist raised frags

 

[victor escobar]

Here in reefforntiers there is an article on this specific issue "browning acropora". It says that not only light has an influence on the acropora's color but feeding. By the way, a very interesting article

 

[mgoblue]

Also how much water is in your system.
I like to hit my acros with strong
rythmic flow every couple of hours.

 

[Dr. Dee]

Yeah there is a good flow on the acro's as Kevin stated. The wild are notorious for turning brown for long periods of time as they adjust to captivity.And i had just got them fresh from Tonga direct.

 

[Slickdonkey]

Here in reefforntiers there is an article on this specific issue "browning acropora". It says that not only light has an influence on the acropora's color but feeding. By the way, a very interesting article

I'd be interested to see this, anyone have a link?

Glad I found this thread, I was about to ask the same question as to why my frags are browning. My water parameters are almost identical to those posted above.

I think I just found the answer. I recently changed the spectrum of my bulbs from 10K to 20K. Even though the 10K bulbs were only used 2 months, maybe the new 20K bulbs caused them to brown. Hopefully they will color up again in the future.

I have a 96x24x24 tank (240 gallons) with 4x250W halides. However, the halides are almost 12" off the water surface. I was considering upgrading to 400W. Anyone think this is worthwhile?

For now I upgraded my spider reflectors to Lumenarc minis and I'll wait a few months to see if that helps. If not I may try moving to 400W, since moving the reflectors down is not going to be practical in my canopy layout.

 

[james734]

I think I just found the answer. I recently changed the spectrum of my bulbs from 10K to 20K. Even though the 10K bulbs were only used 2 months, maybe the new 20K bulbs caused them to brown. Hopefully they will color up again in the future.

Yep I think you just nailed it on the head. They should color back nicely once adjusted. I just got some brown outs and within a couple weeks they're starting to color nicely.

 

[kevinpo]

I would upgrade to 400W bulbs driven by an HQI magnetic type ballast if you are unable to lower your light to 9" from the surface of the water and you plan on keeping high light acropora corals. This is especially true if you stay with 20,000K bulbs. 20,000K bulbs will produce very nice color in high light Acropora but the growth on average is slower.

As a rule of thumb I recommend 250W for tanks up to 22" deep with the lights mounted 9" off the water and 400W for tanks that are deeper.
NOTE: This is for people intending to maintain high light/shallow water SPS corals.

Regards,
Kevin

 

[Slickdonkey]

Thanks Kevin I will consider that.

Besides, what's a few more electrical circuits to add to the four I have already. And what's a few extra bucks on my power bill every month? When you're in this deep it doesn't matter anymore :lol:

Edit: Forgot to ask, are you recommending HQI bulbs or just ballasts? My reflectors are not set up for HQI bulbs.

 

[james734]

If your not setup for HQI then you'll need new HQI reflectors as while as while as new bulbs.. FWIK..

 

[Slickdonkey]

Well I guess that depends on the definition of "HQI". When I hear that term I usually think of double-ended bulbs, but maybe that's not what he means. I think you can use an HQI ballast (i.e. PFO) to overdrive bulbs too, but I've heard this causes a spectrum shift. Not sure if that's a good idea.

I'm not going to move to double-ended bulbs, I can tell you that much!

 

[james734]

LOL.. You might be right. I always thought if you went HQI you had to go HQI all the way. Ballast, Reflector, Bulb..

Swapping everything out will be pretty pricey considering you just bought new bulbs.

Might make the wife a littel upset.

 

[Slickdonkey]

Yeah, I'm starting to wonder whether keeping SPS, or specifically acropora, is really worth the added expense. We're talking 21A of current for my lighting, new ballasts, new bulbs, more heat, etc, etc... Someone kill me now.

 

[james734]

It's always something isn't. This is one exepensive hobby or should I say money pit. Just when you think things are going good something else comes up that you need to spend more money on. But in the end it's only money right...

 

[Dr. Dee]

I agree with kevin on the lighting,As for the 20k it gives good color but its slow on growing. This what i did for my tank. I have 3x250watts two are 14k one is a 20k thats in the meddle and i use two 165 Vho one 03 act and 1 50/50 and now the colors are coming back and now growing.Oh my tank is a 135 show i'll get some pic's later.

 

[Herefishyfishy]

I miss the monkey:lol: