Emerald Crabs versus My Tank?

NanaReefer · Dec 6, 2016

Over the past 2yrs I've had 3. All had died within months of introducing them to my tank.
The body slowly turns white and it's not long after that and they're gone. All from different sources.
Zero issues with any other inverts. Hermits, shrimps and Clam all thriving.
Ideas anyone?

saltyfilmfolks · Dec 6, 2016

It's a big animal and eats a lot more than we think. Most tanks IMO don't have enough of what they need. Some tanks do oddly. I gave up on them for the same reason. I could not figure out with the las one whatvit needed and tried a lot feeding trick to no avail.

Keep in mind I had a green knuckle for five years and a porcelain for four.
It's not an easy animal and def not CUC
And I've never had one that I saw eat bubble algae.

Another thought is because it's considerd CUC and less than, there not well cared for in transit and the Lfs. So by the time we get them there on the way out.

Birddog · Dec 6, 2016

I have had decent luck with them generally speaking, but as Salty ^ above states there big and heavy feeders. I have had outbreaks of GHA as well as Bubble algae and they are eating machines. For example within the last 6 months I had a pistol shrimp that ate my entire CUC... Snails, crabs etc. it took me a while but I was able to catch the pistol and get him out. Without a CUC I had some pretty good GHA. Put in 20 snail and 3 Emeralds and in one week the tank was clean as a whistle. Snails ate all of the "film" algae and the emeralds ate the GHA. I've found that if you purchase larger emeralds they will eat all your algae including bubble. The only time I've not had success with BA and emeralds is when the emeralds are small. The problem with big crabs is they'll eat themselves out of house and home and then you have to supplement their feeding on a daily basis.

Hardmasterflex · Dec 6, 2016

I have two emeralds. I direct feed them as well as leaving dried seaweed out at night for them to munch on.

NanaReefer · Dec 6, 2016

Why do they immediately turn white though? I mean they live for weeks to months but they're body turns white. Even with acclamation.

Frop · Apr 1, 2017

Birddog said:
I have had decent luck with them generally speaking, but as Salty ^ above states there big and heavy feeders. I have had outbreaks of GHA as well as Bubble algae and they are eating machines. For example within the last 6 months I had a pistol shrimp that ate my entire CUC... Snails, crabs etc. it took me a while but I was able to catch the pistol and get him out. Without a CUC I had some pretty good GHA. Put in 20 snail and 3 Emeralds and in one week the tank was clean as a whistle. Snails ate all of the "film" algae and the emeralds ate the GHA. I've found that if you purchase larger emeralds they will eat all your algae including bubble. The only time I've not had success with BA and emeralds is when the emeralds are small. The problem with big crabs is they'll eat themselves out of house and home and then you have to supplement their feeding on a daily basis.

Do you think one the size of a quarter can live in a 2 gallon refugium without feeding? The fuge may get run off mysis. I'm going to cut back on my mysis feeding.

Birddog · Apr 2, 2017

Frop said:
Do you think one the size of a quarter can live in a 2 gallon refugium without feeding? The fuge may get run off mysis. I'm going to cut back on my mysis feeding.

For a short period of time, but dependent upon what's in the fuge to start with I would not believe it would survive long term

Best Fish-Jake · Apr 7, 2017

Frop said:
Do you think one the size of a quarter can live in a 2 gallon refugium without feeding? The fuge may get run off mysis. I'm going to cut back on my mysis feeding.

I had one about the same size that kept crawling on my sps.. I tossed him in my make-shift 3g fuge and he did great! That is, until he ripped up all of my chaeto...

happyhourhero · Apr 7, 2017

I had a stone crab that killed all my emeralds but I just added one back in and surprisingly it took down a few starting out tufts of bryopsis.

Frop · Apr 7, 2017

Best Fish-Jake said:
I had one about the same size that kept crawling on my sps.. I tossed him in my make-shift 3g fuge and he did great! That is, until he ripped up all of my chaeto...

Haha my chaeto grows at a rate of maybe a half handful per week. Was the main issue being chaeto in the display?

ahiggins · Apr 7, 2017

One lived in my sump, feeding off of whatever made its way there, for about 6 months before it died.

Best Fish-Jake · Apr 7, 2017

Frop said:
Haha my chaeto grows at a rate of maybe a half handful per week. Was the main issue being chaeto in the display?

A lot of it didn't get passed the return pump.. some did make it to my dt but it wasn't a huge deal. Most of it got caught close to the surface of my fuge and got burned to hell which released a bunch of nitrates

Frop · Apr 7, 2017

Best Fish-Jake said:
A lot of it didn't get passed the return pump.. some did make it to my dt but it wasn't a huge deal. Most of it got caught close to the surface of my fuge and got burned to hell which released a bunch of nitrates

I didn't know burning the chaeto would release nitrates. Good to know :)