Kevin Kuykendall's (Anemone)
Anemone-Dominated Aquarium

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The one thing that has always impressed me with Reef Central's Tank of the Month selections is the thought and planning that seem to be evident in each tank. Every tank I've seen appears to have been well thought out, with an incredible amount of planning and forethought having been put into equipment choice and placement. Every tank stand looks like a Martha Stewart project. For better or worse, my tank wasn't formed in that mold. This was my first saltwater tank, and as such, represents more of an evolution and accumulation of knowledge and equipment, rather than a well thought out, clear-cut initial plan.

Aquarium Profile:

65-gallon tank
48" x 15" x 20"
Acrylic SeaClear System II with built-in filtration


I started this system in June of 1994 as a mixed reef. I purchased a SeaClear System II tank that was sold as "reef ready." This meant the tank had twice as much lighting as the standard System II tank, so my 65-gallon tank arrived with 60 watts of Normal Output (NO) fluorescent lighting. For those readers unfamiliar with the System II design, the tank is equipped with a built-in filtration system in the rear of the tank. Water overflows into a chamber on the left side of the tank, goes through a filter pad, then onto a drip plate, where the water flows over bioballs before finally being pumped back into the right side of the tank. The store I purchased the tank from also suggested that I use a Fluval canister filter to provide additional filtration and water movement.

Over the years, this tank has evolved away from its original design. In 1995 I replaced the Normal Output (NO) lighting with an Icecap 660 ballast and Very High Output (VHO bulbs). Shortly thereafter, I hooked up a 1/5 hp Aquanetics SlimLine chiller to the Fluval. In 1996 I removed the filter pad, drip plate and bioballs. I modified the bioball area into a mini-refugium, with about 3" of sand, a few pieces of live rock and some macroalgae (Caulerpa sp.). I placed a 15-watt NO tri-phosphor bulb over that portion of the tank to provide some lighting for the macroalgae.

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The chiller, IceCap ballast and APC Back-UPS unit are located
in the tank's cabinet.

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Now the tank is lit by 295 watts of VHO lighting (a 46.5" Actinic Blue bulb, a 46.5" Actinic White bulb and a 24" Actinic White bulb) for 11 hours daily, plus two 15 watt NO bulbs (one actinic and one triphosphor) that run for 12 hours and are used for dawn/dusk simulation and refugium lighting. A SEN 2500 has replaced the Fluval as the chiller's pump, but I still use the Fluval's J-tube (water intake) and spray bar (water return). I also use two powerheads, a PowerSweep 214 and a small Mini-Jet, to provide additional water movement. I have the tank's main return pump (an AquaClear 402) and the SEN 2500 plugged into an APC Back-UPS 400 (a computer backup battery), which will run these pumps for approximately three to four hours in the event of a power outage.

I don't currently use any additives. During my first few years in the hobby, however, I think I tried every type of SeaChem additive ever marketed, along with SeaLab #28 blocks, CombiSan, C-Balance and B-Ionic (and probably a few more that I've forgotten). Several years ago, though, I gave up chasing the "perfect number" and just continued to perform regular partial water changes. I have used cured natural seawater (Catalina Water) since I initially set up this tank, and I now change about 10% every two to three weeks.

Water Parameters:
Temperature: 78.5-80.5º
Specific Gravity: ~ 1.026
Calcium: ~ 240 ppm*
Alkalinity: ~7 dKH
Nitrates: 0.5-1.0 ppm
*This number may be in error - the test kit is very old.

This tank has used some different protein skimmers at various stages in its development. A 4" x 4" opening in the rear of the tank is designed for placement of a skimmer. I didn't initially run a skimmer, but a year after the system's initial setup I purchased the wooden airstone skimmer made specifically for this tank. Several years later I upgraded to a round acrylic tube, made to fit into the 4" x 4" opening, which used a Rio 600 venturi to create foam. This skimmer was slightly more effective than the first one, but was very difficult to service. Three years ago, the Rio 600 stopped working (again), so I finally abandoned the use of a skimmer on this tank.

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A picture showing the rear filtration area that is used as a refugium.

The Anemone Onslaught!

I added my first Rose Bulb-Tipped Anemone (RBTA) in June of 1995. Actually, I had tried a few anemones before, but this was my first success (somehow, my earlier attempts under NO lighting with nitrate readings over 140 ppm were not successful). This anemone split into four clones in September of 1997. After that, my tank's days as a "mixed reef" were numbered. The anemones began to split more frequently and required a larger and larger portion of the tank. Consequently, the other corals were either killed, or were removed to other tanks to save them. By the middle of 1999, my tank had become an anemone species tank.

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Happier times - pre-December 2004 anemone spawning event, my GSM pair spawned every two weeks like clockwork. Orange clownfish eggs can be seen in the picture on the right.

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March 2002 anemone spawning - this was the only clone that could be seen in the tank. The white specks in the picture are anemone eggs.

In March of 2002 the tank experienced its first anemone spawning. About 30 minutes after the main lights went off (the dusk/dawn actinic NO bulb was still on), most of the ten or eleven clones in the tank began spawning. The tank's water became milky (see photo left), and it was impossible to see more than just a few inches into the tank. The tank was also filled with small 1mm eggs, and this was the fist indication (to me) that my RBTA clones were female. Even though the majority of the clones spawned, the only loss I experienced from this incident was the death of all three of my Tiger Trochus snails (the only snails in the tank). Although the clones withdrew and obviously appeared irritated, and the fish seemed skittish and were breathing rapidly, I lost no other livestock. I had a smaller spawning event this past November that killed every fish in the tank except for my male Gold-Striped Maroon (GSM) Clownfish. My losses included a seven-year-old Purple Tang, a six-year-old breeding female GSM Clownfish, a Sixline Wrasse, a Yellow Watchman Goby and a Blackcap Gramma. I also lost nine- and seven-year-old red serpent stars and one of my two cleaner shrimp. This time, though, all the snails survived. I have no idea why this spawning was deadly to the fish, while the previous spawning was not. I had a skimmer running on the tank during the first spawning, but turned it off as soon as I saw the spawning event (I didn't know that none of the eggs could be fertile and hoped to save some of them by disabling the skimmer).

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Present tank inhabitants are eleven female RBTA clones, one male RBTA clone that I acquired from Sanjay Joshi, the male GSM Clownfish (that appears to be making the change to female), a new Purple Tang, a Yellow-Tailed Blue Damsel, and a Purple Firefish that now lives in a burrow with my Tiger Pistol Shrimp. I intend to pair my GSM with a small juvenile when it has completed its sex change.

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I generally don't target feed the anemones, although I have at various times in the past. I feed the fish frozen Ocean Nutrition cubes every one or two days, and the anemones always seem to capture a good portion of that food, so I rarely worry about target feeding them anymore. When I was target feeding, I found that my female clones quickly devoured almost any meaty food, but it seemed that frozen krill was a favorite. The male clone did not seem very interested in krill (often letting it drift off his tentacles), but always accepted frozen silversides. I doubt that gender influences food preference, but I find it interesting that different members of the same species exhibit different preferences for prey and food items.

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The interesting and sometimes frustrating thing about having an all-anemone tank is that the tank is never the same from one day to the next. Beyond the anemones' typical swelling and contraction and splitting and spawning, the clones actually move around the tank. "Happy" anemones will generally stay in place, but with this many clones, some are always on the move. One day I had four clones on the back wall near the spray bar, and the next I had five, with one moving toward the toothed overflow into the rear filtration section (a definite "no-no"). I moved the one near the overflow back into the rocks, and the next day another clone had moved onto the sponge filter of the Power-Sweep. This wasn't a problem I had experienced with my large Euphyllia ancora or Acropora corals that were previously in this same tank. And "catching" problems is not something that one necessarily gets better at with experience - even with over 100 clones produced in this tank, occasionally a clone still gets caught in a powerhead's intake, or shredded through the overflow.

Tips and Tricks

Over the past 10 years, I have discovered a few things about keeping RBTAs that I can share. One of the first problems I had to address was keeping my first anemone in place. It would climb the rockwork up to the rear wall of the tank, then climb the rear wall to the surface of the water, then migrate over to the toothed overflow. I would remove the anemone from the rear wall and place it back on the rockwork, only to have the same thing happen again. I discovered that if I made a rockwork peak that was not leaning against the tank's rear wall, the anemone would migrate to the top of this peak and stop. I've also found that my RBTAs prefer to have their feet buried in holes or depressions in the rock, and that they often prefer to plant themselves on the underside of rocks (in a hole or depression) and then expand upward toward the light. If one has a larger tank, creating a rock mound completely surrounded by sand does a pretty good job of limiting the movement of the RBTA (and any clones you might be rewarded with).

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I've tried several methods for removing clones from the tank: powerhead flow, steel hammer, removal of the rock from the water and ice cubes, among others. With the powerhead method, one points a powerhead outflow at the base of an anemone, irritating it until it moves (one needs to be careful that the powerhead current doesn't tear the main body of the anemone). I don't have many powerheads in my tank, and trying to add a powerhead to direct flow temporarily in a certain direction never seemed to work (the powerhead moved, or due to the number of other nearby clones, caused other potential problems). So this method has never been particularly successful for me. I was told that collectors used steel hammers to tap on the rocks, and the vibrations caused the anemone to release its hold. The one time I attempted this method, I split the rock directly beneath the anemone, and the breaking halves tore the anemone in two (and I ended up with two clones attached to rocks). Another method I tried involved placing the majority of the anemone's rock out of the water while allowing the upper portion of the anemone to remain in the water (hoping that the anemone would pull off the rock and move into the water). After several hours this method hadn't caused any apparent change in the anemone's attachment to the rock, so I gave up. Finally, I've tried the ice cube method - involving placing an ice cube on the edge of the foot of the anemone, causing the anemone to release its hold on the rock. Some folks swear by this method, but personally I found that I went through a bunch of ice cubes (80 degree water will do that) without any reaction from the anemone. The only way I've been regularly successful in removing clones from my tank is by waiting until they are on the tank's wall. Then, it is a relatively easy task to get a thumbnail beneath an edge of the anemone's foot and gently peel the anemone away from the wall. I've found that I can encourage clones to climb the walls by placing the rock they are on against the tank wall, but other than that, I've given up trying any other methods to encourage them to move.

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Side view from the left.

Concluding Thoughts

Even with the threat of a fish-nuking spawning event, or the occasionally frequent need for "clone-corralling," I have never thought of replacing or "redoing" this tank. It still has the original 50 pounds of slab-like Caribbean live rock it started with (which was legal to import back then) and the two or three inches of crushed coral gravel I added in June of 1994. This tank has evolved into a successful system (possibly in spite of some of the things I've done), and as my choice of Reef Central nickname may show, I've grown quite attached to being an anemone-keeper.

Feel free to comment or ask questions about my tank in the Tank of the Month thread on Reef Central.

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