They truly are the cockroaches aquaculture. Once you see one, you must do your best to rid of it. In my experience, aiptasia predators are slow and rarely find their target.The one thing I will say about aptasia is don't underestimate their ability to survive. I'm not debating methods as there are many threads that have that going on. I've dealt with aptasia for many years and it is a battle. My wife and I have tried injecting everything from lemon juice to vinegar into aptasia just to watch them come back with many more. I've seen them survive peroxide dips and come back from over 8 hours out of water. The only thing that truly worked for us was manual removal out of the tank which is very difficult or natural predators. It's always a risk injecting or covering an aptasia and wait a month before you call victory.

