随着海水养殖爱好的发展，越来越多人开始注意到无共生藻珊瑚（azooxanthellate为了尊重原文由此简称为azoox。个人更偏向NPS： non-photosynthetic corals）。 有些人甚至认为azoox将会成为下一个替代SPS的珊瑚养殖最高挑战。厂家开始使用azoox的图片来坐宣传，公司开始推出针对性的食物以及产品链，网络论坛为其设置了新的版块，近期甚至出现了专门针对azoox的社团。不仅如此，在过去的几个月里，活体网店开始专门设置分类版块出售NPS。很明显，市场已经认可了这个趋势和需求。
首先我们需要知道我们面对的是什么：无共生藻，非造礁珊瑚，他们依靠浮游生物，碎屑，溶解在海水中的有机以及无机物为生。知道它们需要什么只是成功的一部分。频繁的喂食以及有效的喂食方式让事情变的更困难。在生产NPS食物方面，两家公司走在最前端-Reef Nutrition & Fauna Marin。两者都不断的通过和爱好者的合作来研发和完善食品以及添加剂来给azoox以及滤食性珊瑚提供他们所需的营养。
添加益生菌（Probitics原著可能拼错了）是另一个控制你营养盐的办法。不管是使用FaunaMarin Ultralith System, ZEO, Prodibio,或者VSV（伏特加，糖，醋），这些系统都显示了他们控制营养盐以及在为滤食性生物提供菌类食物上的优势。固体碳源-生物豆（NP，荷兰豆）的使用更让那些不想手动添加以上产品的人省了不少事。在短时间内NP豆在减少NO3以及提供菌类浮游食物上起到显著效果，并小范围的减少了PO4。这种使用PHA聚合体成分的可生化降解塑料来控制营养盐在这个爱好里还是一种比较新的尝试，长期效应还有待考验。
通过时间的投入，耐心，完善的计划，和饲养经验 无共生藻珊瑚 是可以在家庭中成功饲养的。期待下一期，我想讨论azoox的采购以及选择的一些基础知识以及如何让它们融入有光学作用的珊瑚缸。
An Attraction to the Darkside of Reefkeeping
by Michael Lukaczyn
As the hobby continues to evolve there is an emerging trend that you will start observe with increasing frequency--aquarist attraction azooxanthellate corals (azoox). Some have said that azoox corals are, or very well could be, the next "SPS" in the hobby and the next frontier in reef keeping. Manufacturers have been using their images to sell their products, companies are creating specific foods and product lines marketed directly toward their care, online communities have generated specific sub-forums on their sites, and recently an azoox specific community has been created. It doesn't stop there, as online livestock vendors over the last few months have been adding sections to their sites for the sale of non-photosynthetic corals. Clearly, the market has recognized the trend and demand.
Perhaps one of the most recognized azoox in the hobby, Tubastrea sp.
Photo by Gary Parr
Why azooxanthellate corals? Could it be the attraction of not having to pay your local energy provider a second mortgage each month just to keep those beautiful hermatypic scleractinian corals? That alone could pull an aquarist to the dark side. It could simply be the allure of wanting to step outside the norm in a land of "SPS" & "LPS" dominated aquariums. Either way, azooxanthellate corals are not technically impossible to keep, but will challenge your reef keeping ability, as well as your time and patience.
First and foremost we need to understand what we are dealing with; corals that do not harbor symbiotic algae are known as azooxanthellate and are ahermatypic (non-reef building). Therefore, they rely on sources of plankton, detritus, and dissolved organic and inorganic matter for their survival. Having knowledge of what they need is only one part of the formula for success; frequency of feeding and the method of how it is administered make the formula even more complex. On the food side of the non-photosynthetic world, two companies have stood at the forefront of providing non-photosynthetic aquarists with what they need--Reef Nutrition & Fauna Marin. Both consistently collaborate with the hobbyists to develop and refine foods/additives to support the nutritional needs of azooxanthellate corals and filter feeders.
Upclose and personal with Nephthyigorgia sp. (Chili Coral)
Photo by Gary Parr
Dosing foods by hand, turkey baster or syringe have been traditional methods in feeding azooxanthellates and these methods continue to serve their purpose, but doing so four or more times a day, seven days a week, three hundred sixty five days a year can turn into a daunting endeavor. Automating the majority of your feeding regime can assist in reducing this task. Dry feeds can be measured out and added to a round-o-matic or barrel type feeder over a floating feeding ring, and can be set by the user to broadcast feed the aquarium at their desired interval. Dosing of refrigerated foods is necessary and more complicated. In order to keep the foods consistently refrigerated and to prevent the feeds from fouling in the peristaltic lines, dosing pumps and bottled foods have to be located inside the refrigeration unit. Volumes of foods dosed and intervals of feeding can all be set up through an aquarium controller or a stand alone computerized dosing pump set-up. Even with the best automation, you will still need to get your hands wet with spot feeding corals to ensure individual species needs are met. It is important to document what you are feeding and what you put into the tank. You can easily set up a simple note book, log it into a spreadsheet, or even your daily calendar. Since keeping Azoox corals is largely an experimental affair, having documentation to reference back to is a tool that is vital in keeping track of what has worked or hasn't worked with particular animals and the system as a whole.
Automated refrigerated feeding system controlled by GHL Profilux 3 on author's aquarium
Keeping water quality at optimal levels in a non-photosynthetic system can be challenging due to the constant feeding of the system and nitrate and phosphate control can soon become a husbandry nightmare. Azooxanthellate corals can tolerate mildly elevated levels of waste, but the other inhabitants in your system may not, so attention to pristine water quality is the same as in any reef -keeping endeavor. A well thought out plan has to be developed, evaluated frequently, and adjusted as needed to keep water quality managed. Water clarity is most simply aided by the use of activated carbon. It is an excellent, cost effective method to reduce the yellowing compounds in the water. While using carbon, insure that it is cleaned well to reduce fine particles of carbon that can be released into the water column. Often overlooked due to its complexity and initial set up costs, is the use of ozone. Its ability to improve water clarity and skimmer efficiency makes it an excellent tool to have at your disposal.
Owning an azoox aquarium you will learn to love doing water changes. Doing large water changes two or more times weekly is extremely helpful in managing your system and something I strongly recommend. When removing large volumes of water from your aquarium; it should be done slowly and close to already in tank parameters (temperature, ph, Alkalinity, Calcium, etc). Changing out large volumes without checking parameters of both tank and fresh mixed water is not a good reefkeeping practice.
For phosphate control, honestly, the best method in my opinion is to use Granular Ferric Oxide (GFO) in a reactor. With GFO, phosphates are extremely manageable. Keep in mind that with heavy feeding you will need to monitor PO4 more often than you might be used to since GFO can become exhausted quickly in this type of environment. Lanthanum chloride has also been used successfully as a cost effective measure to win the battle against phosphates. It has become a staple to control phosphates at Atlantis Marine World in Riverhead and select aquarists have also ventured into this realm as well, but please read up well on how to use the product safely and properly. Overdoses of Lanthanum Cloride can quickly eliminate all your livestock in a short period of time, so use caution.
Dosing of Probitics is another method of keeping your nutrients at bay. Whether it is the use of the Fauna Marin Ultralith System, ZEO, Prodibio, or VSV (Vodka, Sugar, Vinegar), these systems have all shown to have their advantages in controlling nutrients in the aquarium and creating a bacteria food source for filter feeders. The introduction of solid carbon dosing via bio-pellets pellets on the market can assist those who don't want the manual obligation of dosing any of the above systems. Over the short short term, they have shown excellent results in reducing nitrates, bacterioplankton generation, and minimal reduction of phosphates. This method of using PHA polymer based biodegradable plastics for nutrient control is still young in the hobby and is one of those areas where skeptical reef keeping should still apply.
Fine example of a beatifully maintained azoox aquarium with the use of ozone, automated feeding and water changes by Mike Cao.
With time, patience, good planning and husbandry practices in hand, azooxanthellate corals are possible to keep in the home aquaria. Looking toward the next installment, I would like to discuss basic stocking and selection of azooxanthellate corals plus integrating them into them to a photosynthetic aquarium.
Brahmi, A.C., Meibom, D.C., Smith, J., Stolarski, S., Auzoux-Bordenave, J., Nouet, D., Doumenc, C., Djediat, I., Domart-Coulon 2010. Skeletal growth, ultrastructure and composition of the azooxanthellate scleractinian coral Balanophyllia regia Coral Reefs 29:175-189
Fabricius, Katharina E. 1995. Flow-dependent herbivory and growth in zooxanthellae-free soft corals. Limnol. Oceanogr. 40: 1290-1301
Fabricius, K.E., Benayahu, Y., Genin, A. 1995. Herbivory in Asymbiotic Soft Corals. Science. 268: 90-91
Richter, C., Wunsch, M. 1999. Cavity-dwelling suspension feeders in coral reefs-new link in reef trophodynamics. Mar Ecol Prog Ser 188: 105-116
Tsounis G., Rossi S., Laudien J., Bramanti L., Fernandez N., Gili J-M., Arntz W. 2005. Diet and seasonal prey capture rates in the Mediterranean red coral (Corallium rubrum L.). Mar. Biol.,
Widdig, A., Schlichter, D., 2001. Phytoplankton: a significant trophic source for soft corals? Helgol Mar Res 55:198-211