[Delphinus]

It seems to me that unlike other species, LTA's prefer a slightly subdued current. Deb has had good success with this species so I would definitely defer to her judgment here. I agree with her and the other posts so far with suggestions for placement, i.e., crevasse, burying foot in sand, etc. If you could create a "bowl" where it could sit and not be blown about the tank that would be good.

I'd consider turning down some of the current (if you have a lot) until it is reasonably established, or perhaps rework some of the aquascaping to create an area of gentler flow. Unfortunately, due to the handling methods during collection/shipping/retail process, anemones are stressed by the time they get home to us, and so sometimes the first while after purchase can be a bit harrowing. They may need to be watched carefully and have us take appropriate steps if something doesn't appear to be working.

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I think there is a potential for interactions between other anemones. Whether this is happening here, is hard to say, and I would have to guess that the answer is "probably not", i.e., more likely due to shipping stress and acclimating to new environment. I think the risk of negative interactions is diminished among larger tanks (more water volume), and, there seems to be no predictability whether two anemones will coexist or not. I.e., it's quite conceivable that you can go for years and years without some kind of latent behaviour suddenly surfacing. That said, I have had trouble keeping anemones in the same system. Keep in mind that my tanks are a lot smaller than some, my largest tank being 75 gallons. I think to be safest, anything less than 100g might want to be "one anemone per tank" (or one set of clonal siblings, if dealing with a splitting species like BTA's) and for tanks more than 100g, only one or two, and watch carefully.