How To Get Rid Of Aeolid Nudibranchs

[creg]

think this is what i have. i noticed recently my zoas havent been opening up much
 

 

[Chad]

If you can remove the colony you can do a freshwater batch. The zoos can handle it but the nudibranchs can't. You can also use a coral dip but in the case of zoo eating nudies FW works just as well. You will still need to examine the colony for eggs and remove them by hand.
 
If you cannot remove the colony you can remove the nudibranchs and eggs by hand (using tweezers). This is a time consuming process that is best done after lights out. There are solutions you can dose the enitre tank with but I've found they are not effective and can be harmful to snails.

 

[creg]

thanks. yes i can remove them and do a fw dip cheers for the advice

 

[Chad]

It's a shame they eat zoos because they are actually pretty beautiful creatures. I've always been able to control them though so it's not a pest I worry to much about, just takes time to pick them out and remove the eggs. Have fun with it and let us know how it turns out.

 

[creg]

i gave the zoas a quick 30 second dip then noticed this little crab and was worried it might harm him too
 

 
did pick a couple out by hand aswell, they are very nice looking

 

[Chad]

You will want to remove him too. Most true crabs are not something we want in a reef. One of the ways to determine is to look at the claws. Crabs with spoon-like claws tend to be okay (sort of) and ones with pointed or scissor-like claws are not okay and should be removed. It's actually good you found him. You can put him in the sump or a small nano tank for fun but I advise you do not...actually DO NOT...leave him in your reef.

 

[creg]

oh thats a shame i dont have a sump or spare tank. dont like the idea of murder though

 

[Chad]

True, but the idea of him ripping apart your corals isn't a good one either.

He may be on that colony to eat it or to eat the nudibranchs but when he's done hell move on to something else to eat! Here's a good link for crab ID's maybe you can classify him a bit: http/www.chucksaddiction.com/hitchcrabs.html

 

[creg]

hes a xenia crab i was told last night, which makes sense as he came with a xenia frag i bought a month ago. still not sure whether he is good or bad.


"Xanthid crabs superficially resemble swimming crabs (see later) but note that the hind legs are of the clinging type in Xanthids not paddle shaped. Over recent years there is one species of crab which has become much more commonly encountered than in the past. This is due to the increased amount of pulsing Xenia spp. imported for the aquarium trade. The white pearlescent Xenia crab is often found ensconced in even surprisingly small colonies of Xenia soft coral. The nature of the beast is difficult to ascertain. Early encounters suggested that the crab was a harmless commensal species perhaps living off the mucus of the coral. Due to the increased volume of encounters with this animal a different story seems to be emerging. That the pulse coral is bothered by the presence of the crab is certain. I have witnessed small colonies shrink in size due to its presence. It could be that larger colonies are not bothered unduly by its behaviour as the disturbance will be shared by most of the colony rather than a small area as in the case of smaller pieces. However, there are reliable reports of the crab consuming the Xenia itself often after the colony has become damaged in some way. For this reason I must recommend removal of this undoubtedly beautiful creature."
 
 
looks like hes going down the toilet

 

[Chad]

If you can turn him into a LFS that would be nice of you. Remember, the toilet is not a proper disposal method. Xanthid's are among the crabs we don't want with only a few exceptions (like the pom pom crab) from the Xanthidae family are okay in a reef. 
 
It's a good thing you found this little guy when you did!