most important info ive ever read about reef anemones
I wish these guys published the raw data, but they surveyed over 100 reefers.
So this is not a controlled experiment, but large enough survey so that it is not merely the opinion of 1 person. I have used it as my guide to all those critical anemone questions several years ago.
Host Sea Anemone Survivability Survey
Over the years, the knowledge of how to maintain even "difficult" corals in an aquarium has expanded dramatically. Unfortunately, the knowledge of what it takes to maintain anemones for any length of time in an aquarium have not kept pace. To be sure, progress is being made, but keeping an anemone in an aquarium for any length of time is still a serious challenge for most aquarists.
Many aquarists desire to experience the Clownfish/Anemone relationship in their own tanks. In their haste, many try to simply add an Anemone to their Fish Only or Fish Only With Live Rock tank in the belief that the anemone will do well. All too often, the advice given to new anemone owners is: "give them some light, an occasional piece of shrimp and they'll do fine." Unfortunately, this is a recipe for disaster.
In early 2009, the Host Sea Anemone Survey was undertaken. Over 100 current or previous owners of various species of Sea Anemones responded.
As with previous studies, this study found no "silver bullet" which guaranteed success with anemones. There were a number of significant items of interest, however. It appears that the Frequency of Feeding has an influence on the anemone's health and longevity.
The Intensity & Duration of Light per Day which the anemones received was also significant. One might think that the longer the light period, the better the anemone would do, but this was not always the case.
One area that seem to indicate a definite trend in the information is the Tank Temperature vs. Anemone Survivability results. It would seem that the popular advice for tank temperatures for anemones is little more than a myth.
The Water Source results were more than a bit interesting, even though, due to the small sampling size of one of the sources, they can't be considered conclusive.
Aquarist Experience vs Average Anemone Survival
Aquarist Experience vs Average Anemone Survival
While it would be impossible for an aquarist with only one year's experience in the hobby to have an anemone which had been alive in his or her system for longer than that, the experience level of the study respondents seems to have a marked difference in an anemone's survival. The age of the tank (cycled with stable water parameters) would, no doubt, be a factor but it is interesting that on average, the more experienced the aquarists, the more often their anemones were fed.
1 year experience: 15 anemones survived an average of 7.5 months.
2 years experience: 23 Anemones survived an average of 11.3 months.
3 years experience: 20 Anemones survived an average of 19.75 months.
4 years experience: 17 Anemones survived an average of 18.8 months.
5 years experience: 8 Anemones survived an average of 34.8 months.
6+ years experience: 33 Anemones survived average of 22.7 months.
Survival Rate by Feedings per Month
The frequency at which the anemones in this study were fed seemed to make a noticeable difference in their survival. The percentage of anemones which were still alive at the time of the study was most noticeable in relation to the frequency at which the anemones were fed each month:
1-2 Feedings per month
36% still alive
4 Feedings per month
66% still alive
15 Feedings per month
60% still alive
30 Feedings per month
92% still alive
Number of Anemones by Species in the Survey and Their Average Life Spans
59 Bubble Tip Anemones
Avg. Life Span 20.5 months
8 Carpet Anemone
Avg. Life Span 20.5 months
12 Condylactus
Avg. Life Span 16.7 months
12 Long Tentacle Anemone
Avg. Life Span 15 months
2 Quadricolor Anemone
Avg. Life Span 32 months
15 Sebae Anemone
Avg. Life Span 12.2 months
There was no distinction by the study respondents in their "Sebae" Anemone species between the Delicate (Sebae, Hawaiian or White Sand) Heteractis malu and the Leathery (Sebae) Heteractis crispa Anemones.
Due to the widespread availability of the Leathery (Sebae) Heteractis crispa Anemones in the aquarium trade and the poor survivability of the Delicate (Sebae, Hawaiian or White Sand) Heteractis malu Anemone, it is assumed that the "Sebae's in this study are the Leathery Sebae Anemone.
Intensity & Duration of Light per Day
The light wattage per gallon of tank water seemed to have an affect on the longevity of the anemones in the study. Light amounts at the lower end (below 3 WPG) shortened the life span by about half. It appears that lighting above 3 WPG and even more so into the 4 WPG range was beneficial, but above 5 WPG didn't seem to add significantly.
The light period per day that was given to the anemones in this study seemed to have a significant affect on their lifespan in an aquarium. As the graph below indicates, increasing the light period from 9 to 11 hours to day was beneficial, while anything over 11 hours seems to have actually had the opposite effect.
Salinity vs. Anemone Survival
The results of the Salinity vs. Anemone Survival test were quite surprising and may just be a statistical anomaly or the fact that most of the popular plastic swing arm salinity testers in use in the hobby are not very accurate. There isn't any apparent reason why an anemone would survive longer at a SG of 1.023 or 1.025 than they would at 1.024. On the other hand, who knows?? We may have stumbled on to something.
Even when the years of experience were factored in to the SG survivability, it doesn't seem to make a significant difference. The 1.024ers and the 1.026ers had an average of 3.4 years experience while the 1.025ers had an average of 5.2 years of experience.
Tank Temperature vs. Anemone Survivability
One area of the Study which did show some definite trends was in the tank temperatures at which the anemones were kept. Anemones which were kept in tanks with temperatures below 76 F. did not fare well at all. Most marine retailers advise to keep anemones at between 72 and 78 F. which would appear to be very bad advice.
In this study, anemones which were kept at 76 to 78 F. lived nearly 3 times longer than anemones kept at lower (71 to 75 F.) temperatures. This makes a lot of sense when you consider that the temperatures of the oceans where anemones come from are in the mid 80's to over 90 degrees.
Anemone Survival Survey - Water Source
In this survey, RO water was by far the most popular source, which is not a major surprise. Below are listed the different water sources in the survey, followed by the number of people using that source, then the average life span of their anemones.
NSW - 4 - 36.2 mo.
RO - 78 - 19.3 mo.
Tap - 19 - 12.5 mo.
Well - 2 - 6.9 mo.
Other - 12 - 12.5 mo.
The huge difference in the graph below (twice the life span) between Natural Sea Water and RO water makes a lot of sense due to all of the extra "goodies" (plankton, trace minerals and who really knows what all else) in sea water should be an advantage. The small number of NSW users in this study makes it difficult to draw any valid conclusions as to its significance. At the same time, providing water from the environment where the animal came from makes a lot of sense.
Host Sea Anemone Survivability Survey - Conclusions
As stated earlier, this study did not produce a "silver bullets" for anemone survival in an aquarium. There were, however some distinct indicators as to what anemones seem to prefer.
Taking into account all of the factors and survey results, if one was going to attempt to keep an anemone long term, the following parameters would appear to be the best:
1. Natural Sea Water
2. Salinity of 1.026
3. Feed once per day
4. 11 hours per day lighting
5. Tank water at 86 F.
On the reef they locate anemones by smell, so sometimes when a captive-raised clown first encounters an anemone in a reef tank, they aren't exactly sure what is going on - just that they really REALLY want to get close to something that smells good 
