That's the interesting thing. In my experience, yes introducing a sick anemone can make another anemone sick. However, it doesn't make all of rh m sick. For example, my blue gig got an infection and died, but my other two gigs are thriving. Same thing with magnifica. I had a purple sick mag touching two other mags, and they didn't catch the infection. I speculate that the infection is within the zooxanthellae, and that's why it doesn't always pass.
I'm interested to hear what
@D-Nak experienced. I've been reading his threads from way back to 2011
I can't clearly explain why, but I also think that the infection site is the zoox, and not the anemone itself. It's almost as if the bacteria is attracted dead or dying zoox, which is why see infections occurring while in transport, when the anemone is adjusting its zoox population based on lighting conditions. The one common trait we see with sick anemones is that they expel dead zoox in pellet form. I've never seen this with healthy anemones. The waste that they produce (all species) typically looks like either partially digested food or is dark and stringy (which I'm guessing is waste and/or dead zoox which explains the dark color, the same color as the zoox pellets). I'm guessing that anemones in transport do not expel the dead zoox but instead hold it inside, which becomes pelleted, and this possibly gives the bacteria time to infect the anemone.
I've found that Stichodactyla nems (haddoni and gigantea, specifically -- never attempted to QT a mertensii together with either of the two) can transmit the pathogen to one another, but not Heteractis to Stichodactyla and vice versa (I've QTed magnifica and gigantea together without issues).
On another thread there was discussion about the type of bacteria that infects anemones, and it's believed to be a bacteria commonly present in salt water. This reinforces my belief that this bacteria is similar to ich (
Cryptocaryon irritans) and is present in nearly all saltwater systems. It takes advantage of fish that are compromised -- typically stress related to collection, holding, and transport. Some fish can fight it off, others succumb and die. I think the bacteria attacks compromised anemones, can overtake some, while others are able to fight it off. Once an anemone is healthy and acclimated, it's hard for the bacteria to infect it. However, there some occasions when we see an otherwise healthy anemone get sick -- this could possibly be from eating bad/spoiled food, the immune system becomes compromised, and then the bacteria attacks.
All conjecture and anecdotal, just my two cents.
www.saltwateraquarium.com
