Just a quick introduction: My father has a 125 gallon long tank with coral and fish. Everything in the tank is awesome: healthy and water is good. We have two main issues thought that we are stumped on. I know the people in this forum will have a answer. We have a issue fish disappearing. We have aiptasia ALL OVER the tank. It came in the system on some Chaeto Algae. So on the the first issue, we have several theories: A bobbit worm, yet unseen. Other fish killing them, but where are their bodies? Maybe the overwhelming numbers of aiptasia are killing them? There is a shrimp with burrows through the sand and has two yellow gobys as cronies watching over him. could this shrimp kill these fish? On the second point, I just ordered 5 Berghia Nudibranchs from the saltyunderground. They will arrive today. I'm hoping they go to town on the aiptasia. What are your thoughts on this approach? Our biggest probelm is with the fish not lasting very long. I will list the fish we have had and the ones remaining. Of course these were not ALL in the tank at once, but over the last year. 2 O-clowns, dead:frustrat: 4 anthias, dead:frustrat: copper butterfly, dead:frustrat: 4 yellow tangs, 3 dead, 1 remains:frustrat::^: 2 maroon clowns, 1 dead, 1 remains:frustrat::^: blue hippo tang, alive:^: 2 PJ cardinals, 1 dead, 1 alive:frustrat::^: several chromis and damsels, 2 remains:frustrat::^: tan colored tang, dead:frustrat: foxface, alive:^: blue spotted blenny, dead:frustrat: many corals, soft and hard which mostly are doing really well. Just as a ending note I will add that the corals are doing great. We've lost a few, but mostly it is due to our lacking of experience. The water and chemicals levels are perfect nearly all the time. 0 on all bad stuff and PH is about 8.1, with saltwater level maintained at 1.025-1.026.