FAQs about Live Rock
Related Articles: Live Rock, Reef
Related FAQs: Live Rock, Answering
Some LR FAQs by James Fatherree, LR
Hitchhiker ID 1, LR Hitchhiker ID
2, LR Hitchhiker ID 3, LR Hitchhiker ID 4, LR Hitchhiker ID
LR ID 6, LR ID
7, LR ID 8, LR ID 9, LR ID 10,
LR ID 11, LR ID
12, LR ID 13, LR ID 14, LR ID 15,
LR ID 16, LR
ID17, LRID 18, LRID 19, LRID 20,
LRID 21, LRID
22, LRID 23, LRID 24, LRID 25,
LRID 26, LRID
27, LRID 28,
LRID 30, LRID 31,
LRID 32, LRID 33,
LRID 35, LRID 36,
LRID 37, LRID 38,
& Non-Vert IDs 1, Tubeworm ID, Polychaete Identification, Live Rock 1, LR 2,
LR 3, LR 4,
LR 5, Curing
Live Rock, Live Rock Selection,
Shipping/Moving, Placement, Lighting, Water Quality, Live Rock Studies in Fiji Collaboration
& Charts, Copper Use, Marine
Landscaping, Marine Biotope,
Sumps, Refugiums, Faux Rock,
Identification of Growth on Live Rock
Can you please advise on what's growing on my live rock in this picture?
Is it mushroom colonization or propagation or a type of sponge growth?
<I'd put my small moolah on the latter>
I am guessing the later maybe due to extra nutrients in the water as I've had a
number of predator fish in this 265 gallon but recently thinned it out with some
<Nice pic and beautiful growth. I'd keep it. Bob Fenner>
Re: re: Identification of Growth on Live Rock
OK. Cool. Thank you as always!
<Ah, welcome. BobF>
Can't ID hair like growth in reef aquarium (SMALLER SIZED PICS)
Hello, ( , they under 1mb each I don't know how to get them smaller without
cropping too much)
I've asked many people to help me id. I've gotten hydroids, Bryopsis, just
<Could be a Hydrozoan, algae, even a Bryozoan. Need to use a microscope... send
along those images>
The one guess that sort of hit a head when she showed me a pic it was a byozoa.
I've been using vibrant Aquarium cleaner 3.5 weeks and it hasn't changed better
or worse... Because I was told by a very reputable LFS that is well known
throughout the Northeast for there amazing Zoanthid and rate acro collections
Told me it looked like either a step of Bryopsis or hydroids.
The one picture of a small 1/2" green plating monti frag that I super glued onto
a larger 8" orange plate Monti... Right in the middle.. as u can see it only
here in the super glue or doesn't grow on the coral. Usually on rocks superglue
and mostly the ceramic and clear with super glue frag plugs....
Thank you and HELP :)
Maybe if possible can bob fenner take a look... I just want an answer so I know
which route to take.... I am on disability I'm 30 I saved a long time for this
use ESV BIONIC FOR ALL 3 ALK CA Mg
Nitrate for last year was 0-1.0but recently 15ppm (this issue I'm trying to ID
had been happening for months months most likely from the vibrant it lowering
nopox to see if I could (only 5ml) Po4 b ranges from 0.01-0.05
Ph 7.8 I just started using a co2 scrubber recently I live on large Hill in
Buffalo NY South of it and we don't have good air flow in our home....
Trying to raise it
Use 30ml day of nopox 15 morning 15 at night
Use a Skimz Monster GFO reactor
2 maxspect gyre 150/250 model
1 mp40 Vortech
1 Vectra m1 Ecotech
S200 cone skimmer 2 years ago model
120 gallon Marineland corner overflow with a r200 Eshopps refuge/sump
1 200 micron filter sock changed well before overflow starts
Mostly Wrasse fairy flasher cleaner (regular cleaner, neon goby yellow line
goby) red cheeked goby
2 Lyretail Anthias 1m 1female
2 tiara Anthias don't know there sex
2 sand sifter starfish 1 large brittle star many smaller ones that grew larger
from hitchhikers 1 marble Fromia for looks
About 20 Emerald crabs
20 turban or Trochus
10 turbo (2 very large black and White checkered ones)
About 100 Stomatella snails started with one hitchhiker)
I have 2 tigertail cucumber 1 is 15+" the other is a baby still only5-7"
And a pink or "edible" cucumber
1 skunk cleaner
1 Scarlet skunk cleaner aka fire it blood cleaner
Mixed reef lps spa few Zoas maybe 30 total polyps of Zoas and palys
<If very concerned I would remove the rock, scrub it clean. Bob Fenner>
Macro ID 7/19/17
Asking for a friend. Need ID on invasive macro, it is over running and killing
corals. No idea origin of live rock. Thanks
<... what is this?! Green something w/... blue dots!? Do you have a means of
sampling, making some microscope pix and sending them along? Bizarre.
Re: Macro ID 7/27/17
I've requested a close up but it's not forthcoming, he says the blue is from his
camera. It's killing off his corals rapidly. Here's an out of water pic.
<... can't discern even the Division (plant taxonomy, akin to Phylum in
zoological tax.) w/o seeing the cellular structure microscopically... Have you
read on WWM re algal control period? Do so. Bob Fenner>
Help ID what is growing on our rocks. 7/11/17
Resize and re-send... your pix are two orders of mag. too big (39 megs...)
Help ID what is growing on our rocks. Without Video
I’m in need of some help identifying what is on our rock. I’m attaching pix to
Temp 77.5 to 78.5
Neptune Apex controller used to control and monitor various things.
We were using Kent Marine Salt. BRS 2 part dosing ~1ml/gal day (Seems a bit high
for a tank with not much in it).
Reef Octopus skimmer,
Reef Octopus vario-s 6 return pump.
1 of the original Gyre 150s
We have been working to get our levels to stabilize, we are there.
This stuff seems to have been there a while, didn’t start to take off until
recently. The pix/vid are before pix. We vacuumed as much as we could 2 weeks
ago, last week our A/C went out. Lights out on the tank, we put a portable A/C
in the fish room and kept the temp about where it normally is. I climbed briefly
to 81, but stabilized at 78.7. Right before the A/C went out we switch salts to
the AquaVitro Salinity salt, about a 100g change.
After the A/C outage most of it went away. I think it is coming back, looks like
a light film on the rock that is starting to bubble.
I was already thinking of changing salts, when our LFS told us he had never seen
what we have before and did not think it was organic that is what pushed me over
William & Pegine
<Mmm; I'd sample a small bit and look under a microscope... You can read re on
WWM including cheap 'scopes. This looks like a pest Dinoflagellate to me...
Sometimes REALLY hard to get rid of; AND not palatable (to fishes, most
invertebrates that eat macroalgae growths); SOME are VERY toxic. Friend Sanjay
Joshi is having such an issue, and we're currently chatting up on Facebook...
Jules (Sprung) gave this useful link: "A Quick reference Guide? Check out this
interesting new site online:
http://www.algaeid.com/about/ ". Denying nutrient, improving ORP... are the
steps to go toward here. Bob Fenner>
strange bags of something 5/20/17
Dear Wet Web Media, I hope you can help me identify whatever these bags are
attached to a rock in my saltwater aquarium. I would like to know if they
are bad stuff so I can remove them before anything comes out. I am
<These are sponges, Poriferans; no worries. Bob Fenner>
Can You Help ID This Hitchhiker?
Hello Valued WWM Folks,
I was hoping to avail myself of your expertise. I am going into week three
of a cure of some air freighted Pukani rock. Results so far are very good
with lots of resurgent sponge growth, and at least one promising macro
But after doing some on line research, including scanning all your LR ID
pages, I can't figure out what the pictured critter could be. It is
stationary, about one inch across, and is soft, almost leathery to the
touch. There is also a slightly larger, more irregular hole which is just
out of view on the top of the photo. Seems possibly indicative of some kind
of filter feeder.
I have a few more weeks of QT, then will start rotating this "fresh" rock to
replace some aging rock in my established SPS dominant 135 gallon reef
system. I am wondering if you could help with an ID and advise if it should
be part of the transfer?
<I'd move it in myself; likely is a sponge or sea squirt... not harmful. >
Thanks in advance.
<Welcome. Bob Fenner>
Question Help! SW HH mystery
I've written a few times before and I apologize for this being more a
question about when I ask my question! I'm sorry!
I have a hitchhiker and I've been on your site and many others for a week
trying to identify. Odds are you'll take a look and know right away and
somehow I've missed it. However, I've taken some good photos of "it" and my
Google Photos app was even kind enough to make an animation of its movement.
That's important because this creature doesn't move, but it moves in place.
It's hard to describe which is why I was wondering since I know you have
data caps on how many pictures are sent in an email, if I could send you a
link to a Google Photo Album.
<Ah yes; please do. Have tried to crop, enlarge, spiff up the pix you
sent... can't make out much>
It would just be a clean Google Photos link, that way I could show you the
animation and a few other photos without losing quality.
I'm asking to make sure this would be appropriate and it wouldn't maybe flag
my email for having a link in there. If you could let me know how to best go
about it I'd really appreciate it!
Taking a chance, I will send one photo of this "thing." The few details I
can think of are, we've had no new live rock, no fish seem to care, I'll try
and attach a photo with another fish to show scale, since two weeks
ago when I first noticed it and took photos it's doubled in length!
I haven't found any photos to match, which I know doesn't mean I haven't
found one in a different color. I know every last copepod and tube worm in
my tank, so a hitchhiker this large and one I can't identify is making me
nuts! It kind of creeps me out too. I've shown my light on it in the dead of
night. Days straight. Never ever moves. But has some sort of
mouth/web thing similar to a vermetid but WAY bigger.
I was unable to find out if those snails come in many different shapes and
sizes. Ours have all been tiny. This one is growing fast and not tiny.
<Some vermetids get quite large. Bigger than your thumb>
Thanks for the help!!! I appreciate any guesses you may have. I've looked up
snails, cucumbers, and gone through almost all your hitchhiker FAQ.
Anything that looked close to it moved, and this one has no moved a
millimeter. I'm stumped!
If you're unable to draw a conclusion, let me know about the Google Photo
Album. I'd love to share the animations of movement which show you this
isn't just a formation on the rock which I believe I passed it over
thinking it was.
Thanks so much again. I really appreciate your time!
<The link to bigger pix, video please. Bob Fenner>
Re: Question Help! HH ID, SW 4/27/17
Per our original email, here is a link to a Google Photos Album of various
pictures of "the thing." Google makes animations combining consecutive photos
together so you'll be able to see the movement just as I did. I would have
thought I was crazy without it!
<... these images are no better, useful than what you sent before unfortunately>
While it seems similar to a vermetid snail, it is so much larger and noticeably
active. It is also growing alarmingly fast. Which you should be able to
see the growth difference in the album. However, it does NOT move.
<A sponge? Vermetids are slow growers and move quickly when frightened>
As you'll also be able to tell in the photos. The fish swim in that little area
right in front of it and don't seem to notice. We have a Kole Tang, Rusty Angel,
Narrow Lined Puffer, File Fish and cleaner shrimp frequently in that area.
An ID would be much appreciated! I do NOT like how fast it's grown and I hate
not knowing what it is! Thank you so much for your help. I really appreciate you
taking the time to look through the photos.
<And you, Bob Fenner>
Re: Question Help! Ongoing SW HH....
Thank you for trying. I really appreciate it. I understand you cannot confirm an
ID based on the photos
<... why don't you shoot a larger file... crop the images?>
and any guess would just be speculation.
If I notice any more growth, we'll remove the rock or place it closer to the
glass for a clearer picture and hope it leads to an ID.
Maybe because I see it in person, I'm really seeing a "worm-snail." I just read
an article in National Geographic about them and thought the thing I'm looking
at seems very similar. The biggest tip off is the web I see it frequently
dangling from it as the vermetids do. My only pause is the size compared to all
National Geographic Article Referenced:
The National Geographic article refers to a specific species. However, I'm
wondering if it's safe to assume this is just another species that grows a bit
<... see prev. corr. NOT a vermetid if growing quickly and not moving>
I took some close ups today of one of my run of the mill vermetid snails, and
picked out nearly identical antenna and I think what was a mouth.
<.... can't make out any of this in your poor images>
So my question is, could I be looking at at just another species similar to the
vermetid snail? I've enclosed a picture to make sure the word I'm using is
correct and not a name given to different species. I still get confused on
various classifications. My other question would be, is it normal for a vermetid
to get that large, even if it's just one? I'll enclose again a picture with "the
thing" and a vermetid for size comparison.
I figure if it walks like a duck... I mean similar body, web shooting out and
being reeled in, it stays stationary, although you did say vermetids can move. I
shined my light on one today for pictures I didn't notice movement. I have seen
them come and go in certain spots but I've never actually seen that tube like
The National Geographic article referred to that species as setting up in a
certain spot for life, which made me think since this one has not moved no
matter how many times I used my light to take photos, maybe it's a relative
of vermetids and a "worm-snail" I've yet to match up.
Thank you again, for taking time to look at the various photographs. I
understand no ID, I just would like to hear from you if my way of thinking is
logical or a little off base.
I've also got a tiny question that should hopefully be an easy one, since I have
your attention! If you want me to rewrite it in a separate email just let me
know and I'd be happy to if it helps with filing the questions correctly on the
I'm having trouble finding information on Green Wolf Eels aka Carpet
Eel Blenny aka Dotty Back Eel, etc. I'm not sure if it's the various names this
species goes by or the Eel confusion. Even on your site I've found
questions and some General information but nothing to really go into the raising
<See WWM Re... Congrogadus is covered there>
There's just little things about mine I'd like to look into or read about to
understand better. They are the only ones I just haven't been able to find real
solid information on. I find it odd since I see them frequently at the fish
stores. I'll see a good chunk of info on one website and then it contradicts the
next good chunk of info. I struggle to find solid information and some of it as
basic as where they are found! If you know of any websites or books or forums
I'd really appreciate being pointed in that direction. They are such great fish
and so impressive, I can't believe more people aren't studying them and
collecting information (if they are, I can't find them!).
Thank you so much again. I always write too much, so I appreciate the patience
in going through my emails and the promptness in response!
<And you, Bob Fenner>
full size crop...
Identification - 2/11/2017
Your image files are too big... have been deleted. Re-size and re-send. B
Sorry, try these
Jordan with you today. You have a beautiful macro-algae in the genus Laurencia,
most likely L. iridescens. I'd be willing to bet you're live rock was in the
Caribbean at some point and picked it up. It's a non-invasive species that I
would be pleased to find in my tank.>
re: Identification 2/10/17 - 2/11/2017
Thank you Jordan!!
Good to hear. Will the Nudibranch (that photo bombed my pics, and also a
hitchhiker lol) be an issue with it?
<Haha, didn't see that guy earlier. Looks to be an Elysia crispata, a beneficial
herbivore from the Caribbean. You hit the hitch-hiker jackpot with this rock! It
shouldn't bother the Laurencia as it prefers filamentous Chlorophyta including
the dreaded Bryopsis>
ID request from a newbie 6/12/16
Good afternoon from the UK!
<And early morn to you from Calif>
I'm a complete newbie who's had his first reef tank for all of two weeks
(still cycling, ammonia ~0, nitrites ~0, nitrates ~20ppm). Your website has
been incredibly helpful in identifying all kinds of life in my tank, but I'm
still stumped as to what this one is, and I was hoping you could help?
It's a white spherical object about as thick as a pencil, attached by a
small point (it moves in strong current), covered in semi translucent
bubbles/blisters. No holes in those bubbles that I can make out.
<I see... well my first guess was going to be that this is some sort of
Ascidian/Sea Squirt... but if no openings... Perhaps Plerogyra?>
I have no idea how much these photos will help you, but they are the best I
<Yes; would like better resolved, cropped...>
The blue/white, cloudy photo is from the first few hours of the tank being
set up. It's gotten smaller in the couple of weeks since then, but the
bubbles on its surface appear to be swelling out now.
Should I be worried? Happy?
<Much more the latter. That such life is appearing (seeded by live rock,
other hard surfaces likely), is a sign/indication that all is well with your
new system. I would definitely keep this life; enjoy it>
[image: Inline images 4]
[image: Inline images 3]
Thank you in advance!
<Welcome. Bob Fenner>
Re: ID request from a
Thank you so much Bob,
I will read up more on your suggestions and (continue to) watch it with
Enjoy your day,
<And you, BobF>
Semi clear coating on LR 2/28/16
I will firstly apologise for the barrage of queries that I will probably be
throwing your way. But you are now my new found source of info, after a sea of
“We are the best” forums that, although helpful, have more “look at what I know”
people than real help.
I have three current concerns regarding my system, two of which you have already
helped me with, but my other, I, nor anyone else seems to have any idea of.
I am experiencing an almost clear coating that is covering most of my LR. The
most accurate description I can muster is of a soft thin cartilage (I’m thinking
<I see this... and need to see some samples, under a microscope... but have seen
a good many such growths... Usually a mix of Monerans and Protists; but mostly
History of my LR
70% dry rock 30% Live.
using aqua forest salt with pro biotic.
Seems to be worse in high flow area
tank is 9 months in but had a problem with phosphates leaching 6-7 months.
coating timescale….the last 4-5 months
I have a suspicion that it is of a bacterial nature rather than algae due to
lack of any colouring. It does siphon off quite easily but the residue left
behind builds up again and I'm back to where I started.
Also seems to have originated on the Dry rock and now spread. Also is inhibiting
any Coralline algae growth.
I have attached a few pictures for a better illustration.
These pictures are taken by me and should you feel the need…..use them for your
site. (if they are good enough :) ) the bubbles in the picture hold no
thanks again :)
<Again; see WWM re microscopes, algae IDs... scrape some off, send us some
photos. Otherwise, DO read re nutrient limitation, the use of competitors,
predators.... on WWM... for mainly Dinos. Bob Fenner>
Identification of possible pest; Pseudocorynactis poss.
Hello! I'm wondering if the crew can identify this which has just appeared in my
<? Why the huge uncropped file? Read here:
Thanks for providing a wonderful resource to the community!
<Welcome. Bob Fenner>
Re: Identification of possible pest
Thanks for your quick response and my apologies, I just took a photograph and
sent it. I read the link and I gather it's either a mushroom or anemone?
Would it be beneficial to remove; is it pest or welcome addition?
<? Search on WWM re the genus... All archived.... we have some 30k users a day....
Brown Growth Under and Around Zoanthids 12/25/15
Hello crew at WWM,
I hope everyone is having a Merry Christmas!
<And to you and yours>
In the attached
photo, I’m trying to identify the substance that is spreading on the rocks near
the Zoanthid in the middle of the picture. It is brown, translucent and looks
like it has tubes with open holes in spots.
<Yes; my first guess is that this is a sponge of some sort. Second would be an
encrusting brown algae (like Ralfsia); third... oh, I see you mention this
It has spread to some surrounding rocks and has grown on top of some green macro
strands that are attached to the rocks. I am thinking some kind of Tunicate or
Sea Squirt but all the pictures I have seen look more defined than what I have.
I have also considered some type of Sponge or even Cyano but I don’t think a
would be so see through and I think that Cyano would be elsewhere in the tank
and would look more slimy.
<The only real way to tell here is to cut a piece off, look under a
microscope... use a reference. Not likely harmful... and will die back given
conditions that favor other life here>
Could it be somehow related to the Zoanthid being they are the same color?
<Mmm; not likely>
On a side note does the polyp on the white frag plug in the bottom left of the
picture look like Corynactis or Pseudocorynactis?
<Possibly the latter>
It’s hard to see but it has a reddish base, clear tentacles, and white balls on
Thanks in advance for all your help and for the great service ya’ll provide in
answering questions and giving sound advice with all our aquatic needs. It is
GREATLY APPRECIATED!! Jason
<Cheers! Bob Fenner>
Re: Brown Growth Under and Around Zoanthids 12/25/15
Bob, Thanks for the quick reply especially since it's Christmas Eve.
<Heeee! Done shopping, and cooking!>
Re: Brown Growth Under and Around Zoanthids 12/25/15
Since you think it's probably harmless, whatever it is, I'll just enjoy what I
have. I don't readily have access to a microscope or I would love to cut a slice
and look underneath one. Jason
<Oh! Do look into the QX series 'scopes.... think they're still about: Amazon?
Yikes; just looked. There's a BUNCH!
Here's the one I have/use:
Re: Brown Growth Under and Around Zoanthids 12/25/15
Thanks again Bob, Thanks for the link. I like that it is blue and that you can
hook it up to a PC.
<Yeah; and it has two light sources..... AND you can remove the optical bit and
place it where you want!!!>
Maybe I can talk my wife into getting it for me. Once again have a Merry
Christmas and a Happy New Year!! Jason
<And you and yours Jas. B>
Something Odd on my Green Star Polyps
Thank you for what you do for the hobby.
I have had a green star polyps frag for about 6 weeks. I am new to the hobby,
running a 92 gallon corner tank that was a hand me down. I have a 25 gallon
sump, UV sterilizer, media reactor running NPX BioBalls, and a sea Urchin
My GSP is attached to two small LR branches, along on a LR shelf. The LR is the
kind that LFS sells that was made in California and is synthetically impregnated
with the LR bacteria - not a lot of likelihood of hitchhikers.
About 10 days ago I noticed one or two small flowery looking things that come
out when the lights go out and the GSP recedes. People online have theorized
that it is aphasia. Or algae.
<No; looks like Hydrozoans.... perhaps Myrionema genus by name. At any length
you can use this to look up re on WWM, elsewhere>
I have taken it out in an effort to tweeze it away, but only got a small piece.
I also see many new little white conical sponges on the frag mat. There or some
of these on the other side of my tank as well. I have attached one high light
and one low light picture of the GSP.
Are the sponges bad? Are they bad in the tank? Do you have an opinion about the
"stalk" coming out of the frag?
<Sponges not likely bad>
I cleaned my sump last Wednesday, when I did see one Aiptasia (no doubt about
it) and I removed the carbon filter bag that it was attached to. I am thinking
of getting rid of the whole frag, unless you think this is a benign thing on the
<Not benign; unfortunately. Read on!>
Thanks and Happy Thanksgiving!
<And you, Bob Fenner>
Re: Something Odd on my Green Star Polyps
I will remove the frag at once. Is there any chance that it has not spread
throughout the tank? Or am I doomed?
<There is a chance; and you're not doomed. Sheesh. BobF>
White Fungal like growth 5/26/15
<Hey Tom. Nice pic and circling>
I have found this white cotton-like growth appearing on my live rock recently
and wondered if this is something you’ve ID’d before. It is somewhat
easily blown off the rocks using a turkey blaster so I am assuming it is not a
<Mmm; perhaps a mix of Protists... do you have a microscope... there
are some really handy, inexpensive ones nowayears... w/ nifty USB hook ups.
Covered on WWM>
My aquarium is a 10 year old 125 gallon FOWLR with parameters as follows ;
(PH-8.0 , temp-78F, SG-1.025, Nitrates 25ppm Alkalinity-12dkh, Phosphates-
<Quite a bit of measurable nutrient...>
I’ve never seen anything like it before and it seems to grow rapidly.
Thanks in advance for your help,
<Well; could still be sponge material. At any length, doubtful it/this is
deleterious of and by itself. I would keep swooshing it off and siphoning it out
during frequent partial water changes (weekly). Bob Fenner>
Re: White Fungal like growth
Thank you Bob! I will definitely look into buying a microscope this week. I've
thought about purchasing one in the past and now is a perfect excuse to do so:).
I'm working on the nutrient levels with large water changes and the use of
phosphate removal media. Been a bit neglectful lately and I think that's
probably why the problem started. Regards, Tom
<Ahh! Cheers, BobF>
ID; SW 5/6/15
Do you think you can possibly tell me what this is in this picture?? It's
growing all over some live rock that I bought a couple weeks ago, it seems to
start out as a maroon colored spot and gets bigger and turns into these.
Is it some sort of sponge?
<Likely a sponge (or a Foramiferan); yes. Next much less likely guess is some sort of Red Algae
(Rhodophyte); either are fine; indicative of good conditions. Bob Fenner>