If the anemone is a natural host of the clown fish, finding it in a small tank is of no problem so there is no need to try to force them together. The premise of this tube activity is not sound because of this. I have seen, personally, a wild caught Clarki upon release from shipping bag drove straight into a LTA and promptly got stung and eaten. I only see this onetime in my 38 years keeping salt water aquarium.
I have not done liturature search recently but as far as I know, the reason why clowns are immune to anemone weapons have not been work out.
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