Porcelain crabs

[Kamao]

How many can i have in a 14gallon tank? Current livestock is a gramma loreto. I dont plan on adding more fish.

[animalmaster6]

You can keep many different species or crabs together.

[Arkayology]

They like to live in groups.Put a few in there if you like.

[Urchinhead]

They are filter feeders only. If you don't have DOC in the water column for them then they don't eat.

[mrg02d]

They are filter feeders only. If you don't have DOC in the water column for them then they don't eat.

 

Naw...Ive got them in my tanks and see them going through the sandbed, just like the other crabs, as well as filtering the water. They will eat anything available, but would prefer to sit back, hide, and filter the water rather than scavenge.

 

Matt

[Arkayology]

They are not only filer feeders. I feed mine pieces of meat and pellets. I even see mind grazing on algae once in awhile.

[jeremai]

it's analogous to you guys subsisting on a diet of only oatmeal. sure it could work for a while, but it's far from ideal. porcelain crabs should spend the majority of their time filtering the water. if they spend a majority of the time doing anything else, they're starving.

[swigen]

it's analogous to you guys subsisting on a diet of only oatmeal. sure it could work for a while, but it's far from ideal. porcelain crabs should spend the majority of their time filtering the water. if they spend a majority of the time doing anything else, they're starving.

 

Actually, I think it would be more appropriate to say that a porcelain crab that is seen filter feeding and nothing else would be "analogous to you guys subsisting on a diet of only oatmeal. Several studies have noted alternative feeding behaviors in porcellanid crabs and stomach contents confirm the presence of food collected by non filter-feeding means (Valdivia and Stotz 2006, Kropp 1981, Gabaldon 1979). These findings, coupled with the observations of many aquarists (including myself), suggest that in addition to filter-feeding, these crabs can (and potentially need to) feed using alternative methods.

 

So like someone who eats only oatmeal, a porcelain crab that only filter-feeds may be missing something from their diet (like a big juicy steak!).

 

Jeremai, I don't mean to undermine your contributions. It just seems like there is way too much yet to learn about these crabs (and most marine invertebrates) to conclude in absolutes like, "they're starving if they're doing anything but filter-feeding."

[under the sea]

are these too big for a pico (4 gallon) and do they hide alot?

[animalmaster6]

are these too big for a pico (4 gallon) and do they hide alot?

No and sometimes.

If there aren't any fast, really large fish then it shouldn't hide.

[jeremai]

"they're starving if they're doing anything but filter-feeding."

That's not what I said at all. I never claimed that filter feeding was their sole source of nutrient uptake, just that it's their main source, based on their anatomy and behavior in well-fed tanks. In my experience, a porcelain crab in a 'dirty' tank will much prefer filtering the water column over foraging for food elsewhere. It's how they're designed.

[lakshwadeep]

It would be better to spot feed a porcelain than assuming it would survive by filter feeding whatever is in the water.

 

Also, it is important to note the article by Valdivia and Stotz is about porcelains that are living symbiotically with anemones, which is not as common in reef tanks. Here's the abstract (with my bolding):

The porcellanid crab Allopetrolisthes spinifrons, a symbiont of the sea anemone Phymactis papillosa, shows a suspension-feeding behavior related to flow oscillations (repetitive changes of flow direction). Individual crabs oriented their filter appendages (third maxillipeds) to maintain a concave face upstream, showing a higher frequency of maxilliped movements (flexion) at the start of inverted flow. The crab is primarily a suspension feeder that can ingest host mucus and feces. Contrary to free-living porcellanids, the symbiotic life-style offers access to exposed sites in the intertidal and subtidal environments that are favorable for passive suspension-feeding activities and consequently, an alternative feeding mechanism is not necessary.

 

In both the Kropp and Gabaldon articles, the captive crabs were regularly fed either flake food or brine shrimp nauplii and "mashed fish muscle". All three articles support that filter feeding is the primary feeding strategy, which makes sense considering how developed the crabs' filtering appendages are.

[swigen]

It would be better to spot feed a porcelain than assuming it would survive by filter feeding whatever is in the water.

 

Also, it is important to note the article by Valdivia and Stotz is about porcelains that are living symbiotically with anemones, which is not as common in reef tanks. Here's the abstract (with my bolding):

 

 

In both the Kropp and Gabaldon articles, the captive crabs were regularly fed either flake food or brine shrimp nauplii and "mashed fish muscle". All three articles support that filter feeding is the primary feeding strategy, which makes sense considering how developed the crabs' filtering appendages are.

 

Is the porcelain anemone crab Neopetrolisthes ohshimai not a crab that lives symbiotically with anemones?? In my experience, this is the one most commonly seen for sale. Also, if you read further the Valdivia and Stotz article, they mention that in comparison to porcelains that are free-living, the crabs that live symbiotically with anemones are more specialized feeders. It sounds to me that the authors are suggesting that free-living porcellanid crabs may utilize more modes of feeding than just filter-feeding.

 

I'm not suggesting that filter-feeding isn't their primary feeding mode, just that they aren't exclusively filter-feeders.

[jeremai]

I never said they were. Neither did lakshwadeep.

[vinhle00]

it's analogous to you guys subsisting on a diet of only oatmeal. sure it could work for a while, but it's far from ideal. porcelain crabs should spend the majority of their time filtering the water. if they spend a majority of the time doing anything else, they're starving.

 

I think what swigen is saying, is that the crab isnt necessary starving if its using other ways to eat. To be honest i think anything can happen in this hobby. you will see a lot of weird stuff and unexpected characteristic.

[swigen]

I think what swigen is saying, is that the crab isnt necessary starving if its using other ways to eat. To be honest i think anything can happen in this hobby. you will see a lot of weird stuff and unexpected characteristic.

 

Yes! Thank you.

 

"if they spend a majority of the time doing anything else, they're starving."

 

I'm just saying not necessarily.

[Kamao]

Thanks for taking interest in my topic guys. lol

 

Anyway, i bought one. I couldnt see it the first couple of days, but now its found its sweet spot in the tank. I havent seen it eating flake food, not that i spend most of my day infront of the tank, but it filters the water. Hopefully it turns out well, and if it does, ill buy a couple more.

[1fishmonger]

Thanks for taking interest in my topic guys. lol

 

Anyway, i bought one. I couldnt see it the first couple of days, but now its found its sweet spot in the tank. I havent seen it eating flake food, not that i spend most of my day infront of the tank, but it filters the water. Hopefully it turns out well, and if it does, ill buy a couple more.

 

 

They need phytofest/oyster feast type of foods.Flakes won't cut it. They are filter feeders

[Kamao]

Didnt you read the current discussion in this topic?

[Deleted User 6]

fwiw, i didn't feed my porc and it died.

[lakshwadeep]

I personally have not seen many porcelain anemone crabs in local stores, but wouldn't the high percentage of such crabs, which are rarely sold with their anemones, be a problem rather than advantage since they have been shown to be less likely to use auxiliary feeding strategies? Without anemone mucus/feces, they could be even more dependent on filter feeding.

 

Similar to DHaut, I fed my porcelain, but not regularly. It died after a couple of months. My point is that it is dangerous to assume a nano tank's water column is so full of plankton or other food to support a porcelain crab and that assuming alternative feeding strategies will make up for it could lead to the crab's death.

 

Here is a useful hobbyist article on keeping porcelain crabs, with both feeding and compatibility information.

http://www.reefhobbyistmagazine.com/downlo...df/version9.pdf

[Bodacity]

Hey everybody, I want to thank you guys for this discussion and all the links. My research on this crab may have just begun, but this was a damn good starting line!

 

Thanks again!

 

I RILLY WONT A CRABE.

 

 

For anybody who cares, I have a <1gal pico reef, an I'm thinking about this crab for it. I'm going to put one in my 10gal and see how it does. Based on that, I may get one for the pico. I will feed rotis occasionally, but will also try supplementing. Will post back with results and such

[hooligan_78]

if they spend a majority of the time doing anything else, they're starving.

 

I took that as, "if they spend more time hunting and less time filtering..."

 

I had one for the better part of 2 years, who spent the MAJORITY of his time filtering. Very rarely left his spot in the tank; however, it would not pass up a meaty treat that landed close enough to grab.

[Sub]

I put one of these gorgeous crabs in my tank about a month ago and it has not come out once to feed or look around. I literally put it in the tank, it went to the back behind some rocks and I havent seen it come out. I know its there because I can just see it moving around a little if I use a flashlight and look way under in the back..

 

SUCKS! How do I get him to come out?!

[ecogirl22]

I put one of these gorgeous crabs in my tank about a month ago and it has not come out once to feed or look around. I literally put it in the tank, it went to the back behind some rocks and I havent seen it come out. I know its there because I can just see it moving around a little if I use a flashlight and look way under in the back..

 

SUCKS! How do I get him to come out?!

 

time (and stop scaring it with the "giant moon" shining at it hahaha).

 

Seriously, mine was hardly ever seen the first 4 months. Now i see it everyday! I think they just take some time to get comfy and realize no ones going to eat them:)

 

I've never fed mine, so we'll see how long it lives. It filters all the time, often i see it poking in the sand, grabbing at algae and filtering at the same time (whatever comes up from the sand). I hope it doesn't starve, but honestly, I'm not going to buy buckets pf phyto and potentially crash my tank w/ excess nutrients.