I have a 55 gallon FOWLR. I want to give a history of the inhabitants, in case it's important. The short version is I have a snail die about once a week, and I don't know why. For the snails, I float their bag for about 15 minutes, then I add the snail to the tank.
After the nitrogen cycle, over time I've added the following:
1 Clown Fish (First fish, never had symptoms of any disease, still swimming strong)
1 Coral Beauty (Died of velvet - brought it in to the DT, due to my rookie failure to QT)
1 Yellow Tang (Mysterious death; sea star ate him before I could observe, likely velvet)
1 Banggai Cardinal (Died in QT while DT was fallow)
2 Peppermint Shrimp
1 Cleaner Shrimp
1 Chocolate Chip Sea Star
~12 Turbo Snails (Only 3 left in the tank; I've lost 9 in 3 months)
All of the fish (non-inverts) have died except the clown fish, which was the first fish I added. The Coral Beauty entered with Velvet, which eventually killed the Yellow Tang. The tank was fallow for 90 days; but the Cardinal fish died in QT on the ~85th day. The Clown Fish and Cardinal were both treated with CP in QT during the fallow period.
Over the last few months, I've been losing about a snail a week. At first, every time it happened I saw the sea star eating it. Therefore, I assumed the sea star was killing them. Last month, I bought 4 new snails, and he ate three of them that week. So I sold the sea star back to the LFS thinking he was the culprit. Since the sea star has been out of the tank, still almost every week one snail dies. One died while I was on vacation (~1 week), and I came back to a completely empty shell. Another died just a few days ago. The mantel was still in the shell pretty solidly, so I assumed the snail was just hiding. I set it right side on a rock, so the shrimps wouldn't pick at it, but the snail hasn't moved for 4 days. I picked that snail up today, and it smelled pretty strong. Interestingly, the mantel is still inside the shell solidly - it's almost like it got stuck hiding.
The parameters in the tank are mostly fine, with the exception of nitrates being 5PPM (Salifert) and phosphates being 0.17 PPM (Hanna). There is a decent amount of green hair algae (not enough to say an outbreak, and it's not really spreading - all the patches combined probably couldn't even cover one side of my hand, and none are longer than 3/4"). I was hoping the snails would help cut down on the hair algae that is in there, but I can't seem to keep them alive.
I don't think that velvet can affect the inverts, and it should be eradicated. Is there any other type of disease that only affects snails? The shrimp are all fine, the sea star was fine, and the clown fish is fine. Any tips or advice will be greatly appreciated!
