I received new corals a week ago today. I followed Justin Credable's hydrogen peroxide dip guidelines I found on here and Humble Fish.com. Yes, I know putting them in a QT is also supposed to be done but I had been quarantining a rock flower nem, and the day before the new corals arrived, I woke up to nem soup. So, QT crashed and my corals had already been delayed for an extra day during shipping. So I placed them in my DT on frag racks. I found this little guy hanging out on my filter output this morning. I thought it was a sponge of some kind at first but It has moved around a tiny bit. From front to back and all the way to the bend of the nozzle but has not left the nozzle, yet. The best ID I come up with is that it's a limpet? If it is, is it a good or bad one? Should I just pull it out either way? I have searched and read and searched and read. Still not confident about my ID or what to do. So far, I haven't had any other hitchhikers....That I know of! 75 gallon tank has been running for almost 2 years. Thank you for your help. If I need to add parameters and such I will. Kind of felt this was a little long-winded as is..