green balls on my live rock

[pappy112]

Does anyone know what these little green balls are forming on my live rock?

 

[nudilove]

Bubble algae would be my guess, get an Emerald Crab.

 

[reefdude37]

bubble algae

 

[alyssia]

Originally Posted by NudiLove
Bubble algae would be my guess, get an Emerald Crab.

Emeralds can get mean though, you can try to syphon the balls off. Try not to pop them in your tank, this may spread the algae.

 

[nanomantis]

Emerald crabs are a type of spider crab (along with arrow crabs and decorator crabs) emerald crabs are mainly herbavourous however all crabs in general are oportunistic feeders. If it comes across a small fish that is dieing or in the corner of the tank having a rough time, it will make an attempt at catching it. I have seen large emerald crabs do this (over 1 inch in diameter at just the body not the legs). It used its legs to act like a cage as it sat ontop of the fish, pinning it to the ground. The damsel was on its way out anyway so it just acted like a premptive clean-up crew for the body. It was an unusual sight to see, an emerald crab lunge at a fish and catch it.
This behavior is normal for all crabs as even large hermits will definetly eat a fish if given the chance. However Emerald crabs are to slow to catch a healthy fish and the smaller ones a very fish safe. Its only when they get large they get agressive, possibly from sexual maturity.

 

[sea horse]

I used to have those green balls. Until I got a emerald crab!

My pin coshin sea urchin even decorated himself with one!

(along with a pice of sell) The emerald crabs are great at eating hair algey too!