Coral Care

What do SPS need? This is what you need to read

melev — Thu, 17 Mar 2022 17:13:40 +0000

What do SPS need? This is what you need to read

Acropora care

melev Thu, 03/17/2022 - 20:13

Acropora sp. - |LF|a-cro-POH-rah; alternate: a-CROP-o-rah|RF| - a species of calcium-based coral that causes frustration and loss of expendable income but brings joy and exuberance to the more detail-oriented caregivers.

At our club meeting recently, I pointed out how keeping Acropora sp. is often considered the pinnacle of reef keeping. Hobbyists yearn for a full-blown tank that holds these colored sticks that grow into such interesting and unique shapes. The question isn't 'if' you can keep them, but rather 'how long' can you keep them alive to the point of enjoying some thriving colonies. Since they come in blue, green, red, orange, purple, yellow, brown and more, a living Acropora-laden reef can be quite the medal of honor if properly cared for.

I purchased my first SPS (small polyped stony) coral in 2002, and it was a Pocillopora. This little colony, no larger than a golf ball, was my starter piece to see if I had the skill to keep hard corals. Even with much to learn, that coral was a hardy one that tolerated the swings in water quality that my 29-gallon reef suffered from. After a few months, I decided to try Acropora as well, and have been keeping them ever since.

A larger tank tends to have more stable parameters, which is where the saying "dilution is the solution to pollution" likely came from. I can firmly state that a larger water volume does help keep pollution levels down, but when those numbers go south it can get costly trying to get them back where they belong. As hobbyists, the biggest impact you'll have on your reef tank has to do with your husbandry skills. The more often you test the water, the better your overview. You'll be quick to make minor adjustments to keep things on track. Another definition for the acronym SPS is "stability promotes success," as SPS definitely thrive under stable conditions.

Acropora sp. come in various forms, from thick branchy types to very frail skeletons. They prefer rock solid parameters. Water temperatures don't vary much in their natural habitat, tending to move no more than one degree per day. Our tanks may go up and down two to three degrees in a 24 hour period, but with careful planning and good equipment it is possible to keep this variance tighter. Some species do better in cooler waters, but most tropical-based species seem to hold up well in tanks that range from 79F to 81F. This is simple a target range; if you prefer to keep your tank from 78F to 80F or 80F to 82F, likely you will have good results. The tanks that drop down to 76F or lower at night only to creep up to 82F or 83F daily - those corals are doing all they can to handle that seven degree swing on a regular basis. I don't recommend it. Please note, cooling fans coupled with timers can easily stabilize those summer months, and heaters connected to controllers will keep the water temperature 'normal' during the colder months.

Lighting continues to be an important part of Acropora keeping. Metal Halides (MH) are still the standard, but T5 lighting has probably taken up 20% of the market share if I had to guess. T5s are preferred because they emit less heat than MH and don't require a taller canopy. Be that as it may, I still believe some tanks would do better if the T5 bulbs were 7" off the water; closer to the water the corals seem to be affected by what continues to be untested UV radiation which likely leads to the pastel colors we see. Metal Halide bulbs are usually kept 9" to 12" off the water, if not higher in high quality reflectors. Anyone can tell the difference between MH and T5 lighting because of how the display appears to the human eye. MH lighting is a focal point that casts a shimmer effect and the reef tank has bright spots and shadows. T5 lighting appears continuous across the entire reef with no variances. Besides these choices, people are beginning to adopt LED lighting for their tanks, and my best advice is to borrow or buy a PAR meter to get some real measurements and avoid burning the corals with intense blasting light. Lift the fixtures higher or run them for shorter periods, gradually increasing the lighting period over multiple weeks until the corals are acclimated to the change. Keep the lights clean ( reflectors, glass shields and the bulb itself ) as spatter and salt film decrease light output that rob your tank of its intended light. Bulb color is a personal choice, but the general rule is 10,000K bulbs promote growth while 20,000K bulbs provide pretty coloration. A combination of bulbs can get the best of both, if you balance them out correctly. Normal lighting for a reef tank should be 9 to 10 hours per day, incorporating a staggered lighting period to include a 'high noon' duration (all lights are on at once blasting the tank) for a few brief hours will provide the best results.

Coral placement is important. How far you distance your SPS corals from the lighting is something you'll learn with time, but often the best choice you can make is place the corals midway down in the aquarium. If they do well for a week or two, move them up a few inches higher and see if they can tolerate the greater PAR your lighting affords them. Find those sweet spots, and watch the corals closely to see if perhaps they'd be better a little further down in the rockwork. A PAR meter helps reduce some of this guesswork, but if we had rock-solid rules, this wouldn't be a hobby. We like to experiment a little. Once you know the spot is good for a coral, be sure to secure it to the rockwork with 2-part putty or Super Glue Gel. SPS corals tend to grow in more quickly when they are affixed firmly, rather than rocking back and forth in the flow. Corals need space to grow out, and if their neighbor is too close, one will usually lose to the other due to chemical warfare as they sting one another.

Flow is critical with Acropora. They need lots of flow to keep their core clean of any detritus which often leads to dying tissue. Once this tissue or skin is gone, nuisance algae is happy to grow in that dead area, spreading out gradually to consume more territory that erodes away more healthy tissue. Acropora colonies often ship in with 'bandit' crabs, commensal crabs that live within the branches and keep the coral clean. They eat tiny predators and ward off attacks by other livestock, but retreat deeply into the coral to avoid becoming a snack. If you get a coral and find such a crab, it would be best to set that little guy aside prior to quarantining and dipping the coral. Once the coral is safe to add to your display, reintroduce the bandit back into the colony and place it in your reef. Getting back to the topic of flow, this is primarily provided with pumps (Vortech, Tunze, Korallia, or Maxijets - these are the four most common choices in the U.S.) that move the water in the display area. Both Vortech and Tunze pumps allow the hobbyist to program in their preferred flow pattern, with chaotic random surges being the ultimate goal. Laminar flow isn't good for Acropora because the coral will simply grow leaning in one direction. Chaotic flow hits the coral from all sides and coupled with good lighting, each particular species of Acropora will grow into its own natural shape: tabling, pear shaped, bushy, branchy, and encrusting to any solid surface it can find.

Water testing is important for Acropora keepers, who test alkalinity, nitrate, calcium, phosphate, magnesium, as well as salinity, temperature and pH. Keeping these numbers as consistent as possible is the goal. If one swings out of range, such as pH, the coral may stress and release stringy mucous into the water in response. If alkalinity drops too low, tissue will peel off the Acropora, usually around the base. Alkalinity, Calcium and Magnesium are very closely related and must be tested and supplemented continually to replace what the Acropora sp. are taking up from the water. Salinity should always be 1.026sg or 35ppt, and testers should use a calibrated refractometer that was set with 35ppt solution (not RO/DI water!) for accuracy.

Test Type Recommended Parameters matching Natural Sea Water (NSW)

pH 7.9 to 8.3 - this varies from tank to tank; measuring with a Pinpoint Meter or controller is best
Temperature 78° F to 84° F - average reef temperature tends to be ~81°F
Alkalinity 8 to 11 dKH or 2.86 to 3.89 meq/L
Calcium 390 to 450 ppm
Magnesium 1350 - 1400 ppm (or 3x Calcium levels)
Phosphate .03 ppm (leading cause of nuisance algae in your tank)
Ammonia 0 - anything higher is toxic
Nitrite 0 - anything higher is toxic
Nitrate 10 ppm or less (huge water changes bring down nitrates)

Alkalinity and Calcium can be dosed with 2-part buffer solutions or provided with a calcium reactor, and this is a daily requirement for SPS. Magnesium has to be dosed as well, but this one is done every few weeks or longer, based on when the test kits reveals that it has become depleted. Magnesium tends to stay in the water for a long time. Keeping these three in line will keep pH levels up where they belong. Be sure to have current (not old) test kits on hand and use them frequently. Weekly isn't unheard of - its actually a good routine and avoids LRS (Lazy Reefer Syndrome). Be sure to keep a log of those numbers to track trends and learn how to dial in those parameters to maintain optimum conditions.

Phosphate and nitrate levels need to be as low as possible for Acropora sp. Elevated levels stunt their growth and fuel algae growth. Big water changes keep nitrate down, and phosphate removers are abundant to keep that parameter under control. Of course good filtration helps, which is handled with a quality protein skimmer, a refugium for nutrient export, and manually removing any settled waste in the overflows or sump. Rinse out filter socks and sponges often, every three days at least.

Acropora sp. have visible polyps, especially if you have a good macro lens. Each polyp has a mouth that can bring food down its digestive system, and the best free food you can feed this species is fish waste. Feed your fish and when they expel their waste into the water, the corals consume it. Corals that are very pale are usually so because they are starved, either due to a lack of fish or because of amino acid dosing (or due to excess intense lighting for too long a photoperiod). Feed a little more heavily and these corals will color up again.

It doesn't really take special equipment or vast amounts of money to keep these corals, but it doesn't hurt if you have either. Just remember that these are living corals that need your attention and without your TLC, they will decline. This is definitely a challenging species, but anyone that has kept them successfully will tell you it is worth the effort.

Happy reefing!

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Distichopora coral

melev — Wed, 03 Oct 2018 12:59:00 +0000

Distichopora coral melev Wed, 10/03/2018 - 15:59

by Brad Ward

How often have you seen a spectacular colored specimen at a store. I mean, one that knocked your eyes out! Only to find out that it was considered a "Hard to Keep" coral that was shipped in by accident or through mis-identification. Or even worse, bought one of these corals and had it slowly diminish in health and melt away before your eyes. I used to have this happen to me with fish when I started keeping Marine aquariums, and quickly came to the realization that it was better find out as much as I could about that fish before making a purchasing decision. This of course led me to gain knowledge about the habitat, and food source of these individual fish. This in turn made me a much more successful hobbyist, and made me realize that there is always something new to learn. When I started keeping Reef Tanks, I almost had to start all over again, and this time the learning curve has been even steeper! Anyways, I would like to say that what we think of as hard to keep specimens might not be that hard to keep. But rather, that it’s hard to duplicate the habitat where they thrive and grow, the ocean. With that in mind, I would like to discuss one of these corals, and try to delve into what you might do to keep them alive and growing in your systems.

Stylasteridae:
Actually they are members of the class Hydrozoa. Corals of this type have been finding their way into the local stores in the past few months. There are fifteen genera in this family, Stylaster and Distichopora are the two that are most commonly seen by the hobbyist, the latter being more common. Characteristics of these corals include the following; they are colonial, ahermatypic (which means that they are non-photosynthetic), and usually arboresent or tree shaped. Colors are often very brilliant hues of reds and purples. They have small tubular hairlike tentacles called gastrophores which capture appropriate sized food from the water column. Learning a simple important fact like this can help us keep these corals with more success.

Stylaster are found worldwide, including the Arctic and Antarctic. There are 48 nominal species, and an unknown number of true species. This genus has fine branches which grow on one plane, much like a sea fan. The skeletons are quite hard, and the corals color is present all the way through to the core, unlike the calcium skeleton corals. Stylaster is distinguished from Distichopora by virtue of its having cyclosystems, or polyps arranged in a circle just like the fire coral Millepora. These are less commonly seen in stores than Distichopora.

Photo by Marc Levenson

Distichopora are found only in the Pacific Ocean. There are 34 nominal species and an unknown number of true species. This genus has flattened, blunt ended branches which are uniform in size and also growing on one plane like the Stylaster. But unlike the Stylaster, there are no cyclosystems, and the gastrophores are aligned laterally along the edges of the branches. These have been coming into the stores generally in good condition, but are slowly being fouled by slime algae and diatoms. Of those sold, not many if any will survive. You must be aware of what they need to survive, and grow. I have had one for several months that not only seems to be surviving, but also seems to ecomorphing ( or showing new growth to better fit) to its new environment. This is a bright red specimen that came in as an acropora on the CITES sheet, and was listed as “Burning Embers” as the common name. I usually take a dim view when it comes to slips like these, and wouldn't recommend that these as a species should be imported.

My research into the captive care requirements came up with no concrete scientific data that showed what they eat, or if anyone has successfully even kept them before for an extended amount of time in a closed system aquarium. But one book did say that they needed "very small plankton." While not unusual ( as we are really as aquarists, just beginning to learn about the biological side of our systems), it is sometimes necessary to rely on anecdotal evidence in order to get to the point of being able to even begin to provide the correct husbandry required to keep some specimens alive. However, in this case, even the experts didn’t have a clue. The literature that I did read provided a few clues including the fact that they are sometimes common under overhangs or on the roof of caves. Let me play Andy Rooney on 60 minutes here for a minute, does it seem to be that all hard to keep corals are from these locations? If so, I would say to the collectors out there to stop going in caves! I mean, it doesn’t take a rocket scientist to figure out that most hobbyists tanks don’t resemble these areas in the least. Although this does bring up my next point nicely.

If we do want to keep these corals, setting up a system particularly for these species is a good idea. This is called Zonation, and it is an idea that is gaining in popularity. In Volume One of The Modern Reef Aquarium, they discuss different types of systems that might be set up for the care and husbandry needs of certain animals. They recommend a "cave aquarium" for this species. This allows us to mimic their natural environment somewhat. There are some possible ways as I see it to keep these corals. I think that a natural type system that produces a natural food source in the way of phyto and zooplankton is the best way to go when discussing these types of organisms, also heavy particulate feeding might help. The most important thing is that the system is slime and diatom free. I will keep you apprised of my progress with this species. If you have a "hard to keep" coral, please share your experiences with us [hobbyists]!

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Photo-documentary of a Bubble Tip Anemone splitting

melev — Sun, 12 Nov 2017 22:30:00 +0000

Photo-documentary of a Bubble Tip Anemone splitting melev Mon, 11/13/2017 - 01:30

When an anemone is about to split, it's usually pretty obvious. It will elongate, stretching across one or more rocks. It will pull both directions, basically ripping itself in half. When a BTA splits, it's even more important to maintain water quality parameters so the halves can heal properly. Anemones will need a few days to heal, sealing themselves and rebuilding the mouth area that is used to swallow food once more.

March 7, 2004 - 3:05 p.m. - The BTA looks okay, but not nearly as glorious as in the past. It has been in my 29 gallon reef for 22 months under 165w of PC lighting.

March 9, 2004 - 3:02 a.m. - To my surprise, during flashlight duty I saw the foot of the BTA wrapped around the rockwork. This is highly unusual because Bubble Tip Anemones rarely display their foot. Normally it will be deep in the rockwork in a crevice allowing the BTA to retreat deep into the rock for protection.

3:05 a.m. - This is the only shot I got of the mouth stretching horizontally. The clownfish were in the anemone constantly burrowing, and the tentacles tended to cover up the action making it pretty much impossible to take clear images.

6:31 p.m. - 15 hours later, it is stretched out around the rock to the left. It should be noted that since the BTA has been in my tank, once it chose this spot it never moved for 22 months.

8:43 p.m. - The small anemone-to-be already takes shape.

8:48 p.m. - A mass of tentacles continues to hide the action.

8:51 p.m. - This is a view along the top of the anemone. It was possible to see the pink base all the way across.

8:52 p.m.

8:54 p.m.

March 10, 2004 - 12:08 a.m. - The anemone gets serious now that lights are out. The split will occur over the next few hours.

1:10 a.m.

1:11 a.m.

1:12 a.m.

1:45 a.m. - The majority has split, and a ribbon of tentacles about 1/4" thick continues to link the two.

1:51 a.m. - At this point I decided to leave the lights on, because the BTA was very unlikely to abort its plans.

1:53 a.m.

1:59 a.m.

2:03 a.m. - The final piece begins to tear.

2:09 a.m.

2:10 a.m.

2:24 a.m.

2:29 a.m. - I was able to take pictures of a few other things that usually go unseen during the latenight hours. My Blue Damsel came out as if drunk, tangling with the Coral Banded Shrimp (bad idea!), and bumped into various corals. I didn't expect it to make it through the night, but it did.

3:04 a.m. - The foot of the main portion was briefly visible. I've never seen any of this portion of the BTA in the past.

3:05 a.m.

3:10 a.m. - It is down to what looks like fraying fibers. Less than 1/8" wide, it won't last much longer.

3:11 a.m. - The thread is barely visible between the two.

3:41 a.m. - 1/16 of an inch to go.

3:42 a.m. - The baby takes shape.

5:12 a.m. - Two separate anemones, finally. Both rest from the effort, even though the Clownfish continue to rub against their altered home.

5:14 a.m. - The edge of the smaller portion shows the torn area that needs to heal.

March 13, 2004 - 7:11 p.m. - The main section continues to hold the rock as before, and it resembles a backwards 'C'. I wondered if it also would split into two smaller ones, but that has not occured.

7:12 p.m. - The torn edge close-up.

7:14 p.m. - After three days, the proud parent and its 'clone' remain near one another.

For the next two months...

The BTA, the main or larger section, stayed in that same position, and even split another piece off near the top. Unfortunately, that new clone did not survive. It was deep in a hole and I didn't try to feed it. Expecting it to come out when it was ready to eat, I waited too long and it dissolved and died. Two days later while blowing off the rock, I found the residue which I removed with a turkey baster.

After that occured, I made it a point to feed the main BTA every other day, as well as the clone. Since the larger section was still spread out, I fed it at several spots, hoping to get food to each section. The mouth seemed to exist along the entire stretched section, but bristleworms would come out and take the food away. It was very frustrating. On top of that, my two clownfish were constantly active in the anemone, inhibiting its feeding process.

I was able to catch the baby A. Ocellaris and put it in the refugium for the duration. It was impossible to catch the True Percula though. I used nets to protect the BTAs during feeding time, or any other object that would keep them unbothered for an hour. Here is one example on 4/26/04:

The baby clone has grown slowly, but the main one seemed to shrink more and more. About 5/15/04, I wondered if maybe the parent would die and the baby would replace it. A week later, things finally took a turn for the better.

5/21/04 - The clone is visible on the left. The upper portion of the parent enlarged, and the mouth appeared to tear again.

The mouth (white tissue) would extend during feedings along this smooth area.

5/23/04 4:11 p.m. Only a little bit connects the two sections. It won't be long now, right?

5/24/04 1:02 a.m. Still connected nine hours later, as seen in these images.

5/24/04 2:32 a.m. DONE!

5/24/04 - Three BTAs now share this section of Live Rock. (Left, Bottom, and Right)

The end result after almost 11 weeks: Three individual Bubble Tip Anemones now co-exist in my 29g reef. My job is to feed them well so they can grow to be healthy BTAs. Interestingly, it was exactly 2 years ago this month that I bought this BTA. Now looking back, I've watched it morph not only in shape but also in color; I've watched it spawn; and finally watched it labor to split itself into four individual anemones. It truly is a fascinating creature that I have had the pleasure to experience.

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What does RTN look like?

melev — Sun, 13 Aug 2017 12:18:00 +0000

What does RTN look like? melev Sun, 08/13/2017 - 15:18

Some ask "What is RTN?" It is an acronym for Rapid Tissue Necrosis, which means the tissue is dying fast. Ever heard of 'flesh eating disease' on shows like ER? It has to be cut off quickly before it gets into your entire body. Acropora suffer from RTN, and it just happens seemingly for no reason whatsoever.

Here's a lovely piece.

And then a week later I saw this:

Basically, the tissue begins to look very thin, and just sloughs off the coral skeleton in flakes or disintegrates. Here are a series of pictures of it, taken out of the water. I removed it so it could be fragged, cutting off all the healthy pieces in hopes part of it might live. While out of the water, I took a series of macro shots just in case there were parasites I was overlooking.

Here's the core, 24 hours later.

Sadly, the fragged sections didn't give me much hope.

I hope these pictures help others in identifying this situation in their tanks.

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