horseshoe crab

[Dan9]

I was looking at one yesterday at my LFS. The guy there told me they sift sand well and leave fish and corals alone and they stay fairly small in my size tank. I was wondering how big they get. I saw on liveaquaria that they get 2 ft. My tank is a 65g and I don't want one if it gets over 4 inches let alone 2 ft. Do they bother snails, crabs, or shrimp? What is everyone's opinion on these guys? Thanks

[rsmith56]

if you wont a wrecking ball in your tank then go for it, if you need something to sift the sand then i would consider a sand sifting goby before the horseshoe crab.

[dsteamn]

They can get stuck under your reef and topple rocks. I have a sea cucumber and a sand sifting star, and they do wonders in my tank. Nassarius snails are good too.

[StephenInVa]

Tank size doesn't have anything to do with how big something will get. I've seen ones on the beach that seemed like they were 2 feet and larger from one side of the shell to the other. It will get over 4 inches in your tank. Plain and simple unfortunately.

What Rsmith said about them being a wrecking ball is pretty true IME from keeping them. Or they end up dead and decaying after one of the rocks they tumble over falls on them. Never had them bother any livestock though. Corals, fish, inverts, or otherwise. They just bulldoze around the tank completely oblivious to what they run into or knock over. They did a nice job on keeping the substrate turned over. But not worth it IMO.

[supervdl]

they are bulldozers and get too large for the normal reef tank. IMO the horseshoe crabs should be kept in a special reef tank that reflects a sand zone environment. That way they have enough space to dig around in the sand.

[graveyardworm]

Fairly safe as far as fish and corals are concerned, but they do get large. Most just eat everything out of the sand and starve long before they get big.

[sanfordbhines]

<a href=showthread.php?s=&postid=8857678#post8857678 target=_blank>Originally posted</a> by Dan9
I was looking at one yesterday at my LFS. The guy there told me they sift sand well and leave fish and corals alone and they stay fairly small in my size tank. I was wondering how big they get. I saw on liveaquaria that they get 2 ft. My tank is a 65g and I don't want one if it gets over 4 inches let alone 2 ft. Do they bother snails, crabs, or shrimp? What is everyone's opinion on these guys? Thanks

I have had one in my 75 gallon for 1 year and 5 months. It has doubled in size from 1/2 inch to 1 inch. It has been very good for me. Very fun to watch. They will not grow as fast in a tank because their food supply is not as plentiful as in the wild. I have a good supply of bristleworms in my sandbed and I drop in little bits of krill every once in awhile.

I think the key to keeping these is to have enough of a sandbed for them to look through. If most of the tank imprint is liverock the Horseshoe crab will have less odds of surviving a longer period of time.

They should not bother small snails or shrimp or hermit crabs.