I’m in Brooklyn myself and I assume the LFS that sells $350 Gem Tangs is Country Critters, where I bought mine, lol. Once or twice a year, they’ll get a huge shipment of Gems and lower their price to $250. I usually make a trip out there once a month.
Also great story about the crab! My only question is if the crab might be a danger to the fish (if he can catch them)? As far as predation on snails, I think it’s natural for CUC population to fall off over time, though you certainly wouldn’t want them targeted and eliminated, the same concern could be the case for an urchin. Crabs are opportunistic feeders, and unless they’re a reef safe species, anything could be on the menu, including sleeping fish.
As far as urchins, Astropyga Radiatas are beautiful and every bit as effective at algae control as tuxedos/collectors/pincushions, but be aware they grow rapidly. I had one a while back, got it when it was 2” and within months it had grown to 6”.
A few other algae grazers/CUC to consider which would be challenge for the crab to eat:
- Limpets, Stomatella Snails, Abalone, Cowries or Chitons. They are fully covered by their shells and bear down strongly when attached and attacked.
- Hermit Crabs. Can retreat into their shells.
- Pitho Crabs or Emerald Crabs. Pithos are great and relatively large (still 2” max). Emeralds are a little slower at algae control, but also diligent.
Dosing Phyto might outcompete the algae for nutrients, but since it seems you feed the crab heavily, this might be futile.
Yep… country critters… I had been debating whether or not to actually list them. time I went was over my thanksgiving break. What a selection! Also, just want to say, it’s been several months and my mind is still blown by the fact that despite being new to the hobby, during my visit there, I was fortunate enough to see a Dr Seuss Soapfish in person!
By the way- you gave a bunch of recommendations about other types of snails. I’m not sure that you fully understand what I mean when I say my crab eats snails, so allow me to elaborate. I believe that from my explanation, you think my crab uses positioning and intelligence to predate my snails. The same way that a harlequin shrimp might flip over a starfish to make them vulnerable, or a hermit crab might force its way into the aperture of a snail shell (the opening).
My crab is a bit of an idiot and certainly isn’t capable of finessing his way into eating a snail. However, he is capable of using brute force. This is what a snail shell looks like when he’s done with it:
He brute forces his way into each layer and strips out the meat entirely; trochus shells kinda look like a Christmas tree worm fan by the time he’s done with them.
So I guess the question I need to ask is which CUC snails are known for having the toughest shells? When I left my crab alone for winter break, I purposefully added a handful of
mercenaria mercenaria clams so that I left him with food to access but didn’t just dump already decaying matter into the tank. A few of the clams he ate, but the ones that acclimated the best to the tank, closed tightly, and buried into the sand, he hasn’t broken into despite several attempts. He can certainly crack into most mollusk shells but he’s shown he gets discouraged by the thicker ones and eventually ignores them. If, say, conch or cowries were to have substantially harder to break shells than my trochus, there is a real chance he’d end up leaving them alone after an initial failed attempt.
Also, as for fish, I currently have 2 onyx perculas, a red rooster Pygmy waspfish, and a Catalina goby. The Catalina goby is the latest and most timid addition (not sure yet if it will start getting bolder in a few weeks time) but all 3 of the others have at some point or another made their way over to investigate the crab. He hasn’t attempted to grab them during those instances. Frankly, he’s too slow anyways. Also, I had a skunk cleaner shrimp for about a week but molted and died a few hours after. During its time in the tank, it would get pretty close to the crab when the crab was working on a clam on a half shell, and try to steal a piece for itself, and never once did the crab turn around and try to eat the shrimp.
I’ve yet to start adding corals. I’m a tiny bit worried about my crab trying to eat a softie, but honestly, I think his diet is based on scavenging, mollusks, and snails, and I think it’s unlikely he’ll eat Zoas or leathers or anything like that. For the period of time I had an urchin, he left it alone. Also- im not sure if he would try to eat a sea slug. That being said, I’ve always seen lettuce sea slugs on the rockwork not the sandbed, and he doesn’t climb up onto my aquascape. Lastly, I’ve been considering adding some smaller crabs like Pom Poms or emerald, but I’m not sure if those would be on the menu.
again, I know I haven’t posed much of an obvious question here, but any thoughts are appreciated!
