Emerald Crab - A Detailed Look At the Best Crab For Your Clean Up Crew

July 27, 2016 2 Comments

Emerald Crab - A Detailed Look At the Best Crab For Your Clean Up Crew

As we saw in our previous post, the Emerald Crab was rated the #1 algae eater in a saltwater aquarium. I wanted to dive in deeper in this post about this crab and why this crab is a great addition to your saltwater tank. I'm going to break this post down Q A style for simplicity:

Where Do Emerald Crabs Come From?

Emerald crabs hail from the Caribbean Sea to the Gulf of Mexico. They are nocturnal and will hide in caves and rock during most of the day. While primarily a savager of uneaten food, it is well known in aquariums to eat algae.

What Are They Compatible With?

Emerald crabs are compatible with just about every fish or invert you can place in the tank. Generally, as long as you food sources (waste, algae,and food from an established tank), they should not bother any fish or inverts in the tank. If they are starving, they may go after snails, smaller fish, and even polyps. As long as the crab is well-feed, they should pose a threat to the other inhabitants in the tank. In most cases I have seen of them eating other animals, it was due to lack of food, poor water quality (which lead to drying inverts and fish), or overstocking. 

In a mature tank, normally what we need to look out for are fish that might actually try to eat them. Avoid placing them with predatory fish such as hawkfish, triggers, puffers that are known for preying on them.

    Bubble algae is mainly the algae it is known for eating and they usually end up on a reefer's shopping list the first time they have a bubble algae outbreak and they are recommended on a forum or Facebook group. 

    What Do They Eat?

    Crabs are scavengers and omnivorous. They will happily eat leftover meaty food and clear nuisance algae like bubble algae in the aquarium. You may want to consider supplemental feed if the emerald crab is new to your tank or you do not have enough algae for it to eat in the tank. Dried nori and and pellet foods are good choices for feeding. Nori, in particular is quite a show as you can hand feed it to them and they go nuts when feeding off it.

     

    Will They Really Rid My Tank of Hair/Bubble Algae?

    Yes and no actually. Yes, they will eat bubble & hair algae, but if your tank is infested with a large outbreak you should not rely on an emerald crab being able to remove all of it. You should consider manually removing what you can, reducing nutrients, and then having the emerald crab control and eliminate the leftover. You should also purchase from a store that can attest to the fact that they will eat bubble algae. There are some on-line stores that will guarantee this.

    Is  My Emerald Crab Dead?

    This is a common question for newbies when their crab molts for the first time. Like shrimps, these emerald crabs will shed their exoskeleton as they grow leaving behind a what looks like a dead crab. Often times, the emerald crab will appear back out of hiding after a few days...sometimes a week. Either way, it is best to remove the molt or suspected dead tank as you see it to prevent any nutrient build up.

    Any Other Questions? Leave Us A Comment Below!

    What experiences have you had with this crab? Please leave your comments below or any questions you have.

     

    How Many Should I Get For My Tank?

    They do not get too large - maxing out around 2 1/2" and generally you will only need one or two in a tank. The general guidance has been one emerald tank for every 30 gallons, but this will depend on your rockwork setup and abundance of food in the tank. Overpopulating emerald crabs could lead to aggression among the crabs.

     







    2 Responses

    ASD
    ASD

    August 25, 2018

    Hi There,

    I actually do not sell inverts currently. It would be best to get them from your LFS because you can determine the gender of them by inspecting them. The males look like they have 6 pack abs when you look at their bellies while the female has a rounder belly area. Look for females as they are known for being less aggressive.

    Kyle Dunn
    Kyle Dunn

    August 25, 2018

    hello I am interested in purchasing some Emerald Crabs

    Leave a comment

    Comments will be approved before showing up.


    Also in The AquariumStoreDepot.com blog

    Best Canister Filter Reviews
    The Best Canister Filters for Aquariums (2018 Reviews and Top Picks)

    December 01, 2018

    For those hobbyists getting serious about aquarium keeping, high quality filtration is top of mind for keeping the best fish only and planted tank systems. While hang on back power filters have their place in community community setups, there are setups with heavier demands like planted and predator tanks that require a high end filtration solution. This is where canister filters come in.

    View full article →

    Best Aquarium Heaters
    The Best Aquarium Heaters (Selecting the Best & Designing A Heating System)

    November 19, 2018

    Aquarium heaters are one of the more essential, yet more fail prone piece of equipment that you can add to your aquarium. The vast majority of us in the aquarium keeping hobby keep fish that require tropical temperatures so a heater is a must.

    There are many heaters out on the market and it is very easy to just select a cheap aquarium heater and think you are good to go. The best aquarium heaters are not fail prone, built very well, and will heat your aquarium safety. I will go over the best aquarium heaters and also talk about glass vs titanium heaters. I will also talk about fail safes and how to prevent a tank disaster if a aquarium heater fails (and also what usually fails). Let's get started!

    View full article →

    Saltwater Aquarium Equipment Review - Save 100s (EVEN 1000s) With These Equipment Picks
    Saltwater Aquarium Equipment Review - Save 100s (EVEN 1000s) With These Equipment Picks

    November 06, 2018

    I won't lie to you... Saltwater Aquarium Equipment is Expense! It's easy to find equipment like LED lighting well over $800 that just covers a 2x2 space! Where does this madness end! Check out these top saltwater aquarium equipment picks and save HUNDREDS EVEN THOUSANDS of dollars!

    View full article →