Anybody know if you can keep these 2 successfully in a 30 g. tank? I have never had any problem adding cleaner shrimp in my 75 reef tanks (one also had a lobster), however, when I do that in my small low-light tank, the shrimp dies. I also have a tree sponge, 2 gorgonians, feather duster, and 4 small fish (6-line wrasse, royal gramma, tomato clown, flame cardinal) as well as the lobster (which comes out when I feed the fish) and they are all doing fine.
A tree sponge is doing fine in a nano? Likely won’t long term as you probably need to feed lots of plankton to the tank to keep it going and It would be very difficult to feed it enough and keep it alive. I’d try to identify the type of sponge more carefully, try to find others who have kept it for more than a year without it striking in size and feed it more. Right now I would try to transfer it to a larger tank if you can. (KEEP IT FULLY SUBMERGED IN THE WATER, If lifted into the air there is a good chance it will significantly harm the sponge only making things worse.)
What color gorgonians are they? If yellow and red, then I would say the same thing as sponge, find people who have kept them and learn how they feed, flow and such, and move them to a large tank.
“Reef lobstersâ€ÂÂÂÂÂÂÂ, may come from the reef, but I wouldn’t be so sure they are 100% reef safe. I only know a couple people who have kept them and one of them banned it to a sump forever. I wouldn’t be sure if they could cause issues with shrimp, but I would try googling, looking through wet web media, and trying to find other reliable sources such as an up to date invert book.
Sorry I don’t have a specific answer for you on the lobster, but perhaps you can figure out where to start looking with what is written above.
With Jon on this one, additionally the reef lobster tend to be rock movers, so if you do go that route make sure your rockwork is epoxied/tied together so you don’t get a large landslide in your tank.
I’ve had had tree sponge since 6/22/09 and it has done pretty well. Recently it seems to be making a lot of white meshy substance and breaking up. i thought it was dying, but I picked one of the pieces and stuck it in the substrate and seems to be doing well and the base of the original sponge looks good. It was very tall for my tank. Now I have 3. I squirt phyto, zooplankton or marine snow on them daily as well as the red and orange gorgonians. I read that you have to feed them a lot and very little skimming. Can’t put them in my 2 75 g. tanks because they’re brightly lit and one has m.h. lights.
BTW I’ve had 2 reef lobsters (one in my 75g and one in the 30 - no fallen rocks and they’re not glued.
Knock wood.
I’ve kept a reef-lobster for 3 years now. I’ve had several cleaner shrimp (lost due to other reasons) and a coral banded shrimp. No issues. I’ve yet to have a rock slide (knocking on wood).
granted - I’ve had it for 3 years and I’ve seen it out twice - once when I added it to the tank and again on the floor when I was moving tanks and it made a run for it. It lives inside the aquascaping - occasionally if I crawl under the stand with a flashlight and peek up under the tank and find a spot the sand has been blown away I might see an antaena feeler.
I see mine in my small 30-gal because it doesn’t have too many rocks. During the day, he hides behind the skimmer and as I feed the fish, he slides down and gets a couple of bites. In my 75 gal. I never see him and do not know if he’s still alive. Sometimes I get to see his exoskeleton and know then that he’s still there. I have never seen info that he slides rocks. The urchins do and I believer reef lobsters just dig in the substrate to make a cave.
[quote=“afriede, post:7, topic:2953”]
I believer reef lobsters just dig in the substrate to make a cave.[/quote]
You do realize if a rock is on top of the substrate the lobster is moving and it digs a cave under the rock and the rock is not held up by other rocks… Newton’s law of gravity kicks in at this point. Just making sure. 
The biggest rock an “engineer blenny” can move is probably about an inch in diameter. That being said countless rock slides have been caused by these guys in reef tanks where the rocks were not firmly on the bottom of the tank, just from moving sand and other substrate around.
Yes, I do and I guess they can topple rocks. But they dig very small caves and in my experience no harm has been done - maybe I’ve been lucky.
If you have to do a “rescape” of your rocks or move to another tank it is a good practice to place some of the rocks firmly on the bottom before the substrate.(or move the substrate out of the way)
Shrimp are some of the most delicate things we add to our aquariums. I wouldn’t jump to any conclusions and you’ll likely never know the answer. I still question the “reefsafeness” of the lobster, but I wouldn’t pull him out based on Joe’s and my opinions alone.
It is good to hear you are feeding the sponge well and it sounds like a pretty good mix. Best of luck with it. Would LOVE to see you one day post growth images.
Thanks. Will do some day (requires hubby’s help and he’s no hobbyist.