anyone got any idea

[SteveB111]

heres the deal, over the last few days ive had a bit of trouble. somthings been attacking my star fish, took a leg off both a sand sifter and a small orange starfish. tonight i staked out the tank after lights out and i think i spotted a small gorrilla crab, could he take the leg off a starfish?. More importantly while trying to get the crab out i spotted something else, a fish i think, which i never introduced, about an inch down in the subtrate lying against the glass.its colour was (from the little i could see of it) metalic sky blue and black bands and it seemed to be goby/blennie/eel shaped. i tried to tease it out with a wooden rod but it darted about under the sand and gravel an i lost it. i've never heard of a fish hitching in liverock and surviving before. it seemed to be 2-3 inches long. Guys anyone got a clue, and please dont ask for a photo its impossible its in the substrate bed of the aqurium.I'm baffled.

[dcombs44]

As far as the gorilla crab, I'm pretty sure that it will eat anything it gets it's hands on. I just pulled one out of my tank and tossed it in my sump.

The hitchhiking fish, I have no idea. Best of luck.

[greenbean36191]

A "gorilla crab" could rip the legs off of stars, but I think it's more likely that the stars are on their way out without any help. This is how both osmotic shock and starvation manifest themselves in stars. How long have you had the stars? How were they acclimated? What is your salinity? Have there been any changes in the salinity lately?

As for the fish, it might be one of the various fish known as convict gobies. I've heard of them hitchhiking in from time to time, but I've never seen a picture of them, so I don't know which of the many species that common name is being used for. On the other hand, you may be seeing a pearlfish.

[SteveB111]

thanks for the replys guys, both the stars have been in the reef for over 18 months along with a large blue star with no probs, and the water parametres are mint. im pretty sure i have a crab that has been growing in the liverock and only lately has been big enough to do this kind of damage, 14 months ago i added 4 large pieces of live rock for 40 kg which is very porous i think theres a crab in there.

[greenbean36191]

Any guess how long it typically takes for sea stars to starve?...




About 18 months.

[dcombs44]

I've heard that certain species of stars can take 2 to 3 years to starve to death. I don't think that there are many known details about their feeding habits, espcially linkias. I may be wrong on that, but that's my understanding.

[greenbean36191]

The diet of sand sifting stars is well known. They feed on infauna of specific sizes. For Linckia, their diet isn't really known, but it seems to be something that grows on the LR, and whatever it is they seem to need a lot of surface area to get enough of it. Neither one is going to make it to 2 or 3 years before starving unless it was eating something during a good part of that period.

[SteveB111]

thanks guys, so if the general concensus is that my stars are probably starving to death what should i do. The only problem i've personally got with this theory is that the stars have grown by 1/5 to 1/4 in the time i've had them. so how do they grow while starving? thanks again.

[greenbean36191]

They probably weren't without food for the entire time. They don't deplete their food source instantly. It takes some time, during which they will grow. After that they start to feed on their own internal organs.