Hello, I am new to this site and love what I see so far. Here is my question, I recently inherited a 75 gallon fish tank. I have in there a horseshoe crab and have two chocolate starfish. 1 anemone not sure what kind though my yellow clown fish that I have cuddle with it. I did have an orange clown fish and an arrow crab and another fish forgot the name but anyways seems like my fish are disappearing? I watch them after of course quarantining them and than adding them they are striving and doing great than the next couple of days look and they are missing now my question being is my starfish and horseshoe crab killing them? I seriously need help on this cause I don't understand and don't want to have to get rid of things if this is not what is causing the problem? I don't have pictures to post at this moment

I dont think that the crab and starfish are eating your fish and shrimp...... do you have covers on your power heads... ive had a few get sucked up than i realzied that my cover fell of the powerhead..... other than that i really cant help you out there.... i hope you find out whats going on in that tank... i hate losing fish to unknown causes....

Thank you for the advice you have given me though I have to say when you inherit a tank you are just trying to figure out if anything you have done wrong I have read many books about saltwater and in no means am I finished still trying to learn and understand. I am hoping to keep learning and eventually figure out the proper way of taking care of this wonderful tank. Thank you again

Honestly, this horseshoe crab does look big. They don't usually eat fish tho. Why are they in bags? They are going to die very quickly like this.

Im still living Jdak... im still waitong on my money to come in to get the light-set up for my 150... than i ll hit you up for some good info on tons of different sps and lps corals..... like i said before, all i have now are softies and zoo's and stuff...... but im so F'n excited to get the new lights.....ill keep you posted.....

I'm sure you have a hood right?

I know this is a late response, but I'm hoping I can be of help.

The very first thing that comes to mind is Mantis Shrimp. If you have fish that are disappearing overnight, and there are no signs of any carcasses or body parts, you quite possibly have a Mantis Shrimp living in your rock. Another possibility, and one that is easy to check, is they might be in the overflow box...they can ultimately end up in the filter. My money would be on the Mantis Shrimp though.

No way your Horseshoe Crab or Chocolate Chip Stars are eating the fish. You do not mention having any kind of shrimp, i.e cleaner, coral banded, etc. The reason I mention this is because if you are having fish die, these shrimp could be eating the carcass but you quite possibly would see some remains.

Now back to Mantis Shrimp. These predators are common hitch hikers on live rock. They are a nuisance that can wreak havoc on a tank. I will not bore you with information on how to rid your tank of this creature as there is a plethora of information out there discussing Mantis Shrimp. Just do a google search. I will say this though...these creatures are highly intelligent, have great eye sight and will test your patience. If/when you attempt to capture it, do not sit anywhere hear your tank. He will actually see you before you see him and probably will not come out to get trapped. And if your first attempt is a failure, future attempts will increase tenfold.

Good luck.