Lawnmower blenny, comp.   7/12/08
Good day,
<And to you Barb>
We just purchased a lawnmower blenny a week ago. Strange occurrences are happening now, we have had 3 fish die and one of my oldest blue damsels was bitten (mysteriously) two days after lawnmower blenny arrived. Are lawnmower blennies aggressive
<Yes>
and is it possible for them to have killed my sleeper gold head goby and bicolor blenny?
<Yes>
Also we found our Scopas tang dead just a few days after he arrived.
We moved out a few other fish because we thought they were the culprits, but they have been out of the tank for two days and tonight we found bicolor blenny dead.
I find it odd that we did not have problems until he/she arrived. Please give me advice. I want to move him and take him back for a refund would you agree?
<I would return this fish... or plan on not having much in the way of life that lives near its domain or competes with it for filamentous algae. Please read here: http://wetwebmedia.com/algaeblensart.htm
and the linked files above, part. "Compatibility">
Thank you for your time.
Barb
<Welcome. Bob Fenner>

Re: Serpent Star Question, and Blenny question
Sara, please read down in the email I think you missed the part about the Lawnmower Blenny, that's who I was asking about him getting along with a Shrimp Goby due to similar shape, (not the Foxface) :)
<Oh, I'm so sorry I misread your email. In a tank as big as yours, the two fish should be able to find their own spots and be comfortable. However, there are no guarantees here. Please see:
http://www.wetwebmedia.com/blencompfaqs.htm
Best,
Sara M.>

Blenny And Mandarin Dragonet Compatibility – 10/23/07
Good evening crew!
<<Good morning Sebastian!>>
Hello again Eric!
<<Cheers mate!>>
I hope you had a great weekend and this email finds you well.
<< Thank you...always have good weekends... >>
Thanks again for all your help and patience through this process.
<<Quite welcome>>
I think having this reef tank has been a lesson in humility for me. I learn so much everyday and realize you can never know enough.
<<Indeed>>
Well, first, I freaked out about nothing with the Copper-Safe issue, no idea why that coral banded shrimp died, but nothing else did.
<<Is very probable it simply died of “old age”>>
All corals and snails are doing great and re-encrusting and looking very nice.
<<Excellent>>
I finally reintroduced my remainder fish into the main display on Saturday night. The only survivors were my beloved purple tang, the black saddle back, and the pajama cardinal. These were the fish I was very attached to and I am happy they made it through. I treated for 3 weeks with Copper-Safe and then left another week in the quarantine tank. The main display was fishless for 4 weeks.
<<Another two weeks would have been better but, we’ll see...>>
The fish look so nice and healthy now!!
<<Yay!>>
The tang looks almost like velvet, very rich dark purple almost shiny. Well, I decided to give a clam a try and so far it has been in the system for a week and it's doing great. Attached to a piece of rock and I inspected very meticulously and there were no Pyramidellid snails and such. It is great and colorful.
<<Very nice>>
My next question, I wanted to introduce more fish so I bought a .75" black saddleback to hopefully become a mate for my older one that is about 2 1/2", 2 skunk cleaner shrimps, and a Mandarin dragonet. I have close to 100 pounds of live rock with plenty of bugs in them since I often see miniature molted exoskeletons floating around and even see little crustaceans around the rocks and such.
<<Let’s hope it will be enough... Do try to interest/train this fish to frozen Mysis/reef plankton (soaked in Selcon) is possible>>
He looks great and healthy but I am afraid to keep him in quarantine, what will he eat??
<<Indeed...this is one of those situations/species where it is best to place the fish directly in to the display tank>>
Should I introduce him into my display?
<<Yes>>
I am so paranoid of adding anything in there without quarantine because of my encounter with ich. What do you recommend?
<<Perform a 10-15 minute (shorter if the fish appears overly stressed) freshwater dip that is aerated and has been temperature and pH adjusted to the display. And just to mention – The freshwater dips (before and after) should also be a part of your regular quarantine procedure>>
Also, I saw a Salarias fasciatus blenny,
<<Are pugnacious and quite territorial towards fishes occupying the same habitat (substrate dwellers) or sharing the same feeding habits (algal grazers)...maybe not such a good addition with the Dragonet...and may even go after the Tang if food/space is in short supply. Please read here: http://www.wetwebmedia.com/algaeblensart.htm >>
however, I have read he could hurt corals and clam?
<<I don’t consider “any” Blenny species as particularly reef safe, though blennies of this genus are likely more so>>
What do you think?
<<I would be inclined to reconsider>>
Will he compete with the Mandarin for food?
<<Shouldn’t...but may not like the Mandarin nosing around as it searches for food>>
Should I have just the mandarin and return the blenny?
<<Is the safe choice>>
I just want to make sure I am going on the side of caution and rather ask before hand rather than send one of those depressing "I screwed up" emails.
<<Mmm, yes...but the research should be done “before the purchase”>>
Right now the blenny, Mandarin, and tiny clown are on quarantine. Thanks again for the help, I will be looking forward to your reply.
Sebastian Nunez
<<Happy to assist. EricR>>

Ich and fish compatibility... Algae Blenny... in too small a world 10/16/07
Hi Sara (or whoever takes this question...)
<Hi, Sara here.>
I wrote a while back about my Ich problem. The surviving fish have been in QT for 6 weeks and I'm about to reintroduce them to their old home.
I've got a couple questions for ya -
I've got that 29g BioCube thingy and have been doing fairly regular (small) water changes on it (about 2 gallons every 1.5 to 2 weeks). What do I have to do to take care of the algae that's popping up in my tank?
<Well, you should be doing much bigger water changes (closer to 30% or in your case ~10g).>
Every time the water gets tested, it comes back fine. The lights aren't left on all the time, and it gets no direct sunlight. I now have 5 snails in there, but to get it all off, I have to SCRUB the glass almost to death (ok, it's not alive, but you get the point.) I just bought an Algae Blenny (I had one before, but no algae then - I think he starved.)
<Please note that water can "test fine" *because* the algae is using all those nutrients.>
Second, and final question, can I introduce an Engineer Goby to the mix, or will the Watchman fillet him?
<They should be fine together. The watchman goby doesn't usually attack fish of other species. Please see here:
http://www.wetwebmedia.com/shrimpgobies.htm
and maybe here:
http://www.wetwebmedia.com/gobycompfaqs.htm>
Thanks again for your help and one hell of a website!
<Thank you :-)>
Paul
<Best,
Sara M.>

Quarantining Lawnmower Blenny & Feather Dusters 8/7/07
Hi Guys & Gals on the Crew!!
<Kerry>
Four days ago, my hubby and I put a Lawnmower Blenny (XL according to LFS) and 2 Sabellidae Feather Dusters
<Might be eaten...>
into quarantine (20 gallon tank) and plan to add them to our existing display tank (90 gallons) when they pass quarantine in 4 weeks. "Benny" plowed through both green and purple seaweed on a clip (but turned his nose up at the red; our Regal Tang doesn't like it either), so he has been eating. Today we noticed him (?) nibbling at the tube of one of the feather dusters.
<Yes... can be trouble>
We assumed that he is doing what he is supposed to; grazing algae, but made a mental note to keep an eye on things. I returned to the room a short while later and noticed that he had (apparently) dragged the poor thing over to the PVC tube where he has taken to hanging out. I pulled it away, turned my back, and when I looked again, he was out of his tube "mouthing" its head (I won't assume that he was nibbling it, but I am suspicious).
<Me too>
Temporarily, I've put the feather dusters into protective custody in a nursery tank that I've set onto the bottom of the tank, knowing that this is far from an ideal or permanent arrangement.
<Okay!>
I've looked for information on the diseases of these worms, but can't seem to find any particulars (even consulting two of our "bibles", The Conscientious Marine Aquarist and Reef Invertebrates; The Natural Marine Aquarium Series). I've Googled the site and can't find exactly what I'm after (although it may be there and I'm missing it).
<I don't think we have much... nor is there much re tubiculous worm health... period>
So...here is my one quick question (after a long winded introduction). If this behavior continues after couple days of separation, and we choose to get the feather dusters into our display tank sooner rather than later, is there a great deal of potential for disease from them?
<Yes... I would do this as well. Not likely to be an issue of disease transfer here... But very likely to be continuing trouble with the Blenny...>
The site is awesome; hubby and I both use it all the time, and we've consulted it over and over again as we have gotten our "feet wet" in salt water.
Thanks, Kerry
<Life to you my friend. Bob Fenner>

2 Lawnmower Blennies in same tank.
Two weeks ago I purchased a Lawnmower/algae blenny. I acclimated the fish and put him in my 120G. He seemed happy. The next day I could not find him. The whole week went and I still could not find him. I took a flashlight and checked the rock, the overflows, and the sump. No fish. Assuming (key word here) that the fish was gone I purchased another blenny the next weekend.
This (the new) blenny has been happy in the reef for the last week. He is doing fine after a week and I see him in the main tank.
Last night while watching the tank I saw something in one of the overflow. Guess who !!! Yep, lawnmower #1.
<Mmm, lucky... on both your parts>
Can I have two of these guys in the main 120G tank?
<Maybe not... this is a great fish to watch underwater in the wild (and in fish tanks!)... constantly harvesting the area about it... aware and chasing, being chased by other Atrosalarias fuscus (and often other wanna-be algae eaters) in "its" territory which can be a square meter to a few square meters (depending principally on size of the individuals, availability of foodstuffs)>
LOVE the site - keep up the good work!
<Will endeavor to do so. Thank you, Bob Fenner>
 Andrew Culross

Re: 2 Lawnmower Blennies in same tank.
"Maybe Not" - Don't have a good feeling about this. I have another 29G tank in the basement. Would you put him there or risk the 2 of them in the 120 with plenty of foodstuff (at the moment)?
<Well... my "stock" response is that this species "needs" about a sixty gallon system to support one individual... Please see here: http://www.wetwebmedia.com/trublennies.htm and the linked FAQs beyond... if your 29 has a bunch of algal growth on a bunch (love that term) of live rock... and the specimen is smallish... will likely do. Make sure the tank cover has no holes large enough for the animal to launch itself out of. Bob Fenner>

Re: 2 Lawnmower Blennies in same tank.
No LR in the 29G. Some algae growth. I realize all individuals are different but I'm trying to make an informed choice here. If I put him in the 120G there will be no chance of retrieving him. Do, in general - in your experience, lawnmower get along or fight?
<They almost always fight... unless there is sufficient space, food, hiding/visual get-away places... If there is not a real need for another, tolerance of angst on your part, I'd trade the one in. Bob Fenner>
Thank you.

Blenny nipping fins
Hi.
<greetings>
I have a lawnmower blenny that has nipped off the majority of my yellow tangs fins. 
<they are territorial although not usually to this extent>
he doesn't do this to any of the other fish. He is well fed with algae and has plenty of rockwork in a 120 gal. 
<indeed, it has nothing to do with feeding, but rather aggression>
If you have any tricks please pass them on.
<they most likely need to be separated. Anthony>

Blenny compatibility question
Hi Bob,
I am considering getting a Lawnmower blenny for my 120g reef tank. I also would like to add a Midas Blenny. Would the two fish work out ok in this tank or would one try to harass/kill the other? Thanks,
<In this size, type system, should be no problem. Wish I had videotaped the many Salarias fasciatus interactions I saw earlier this month in Pulau Redang, Malaysia... amongst themselves and a few Atrosalarias fuscus... pretty much ignore all non-algae eating fishes. Bob Fenner>
Dave

Compatibility of Wrasse and Blenny
Mr. Fenner,
I was hoping that you could advise me on how well a Salarias fasciatus (lawnmower blenny) and a Pseudocheilinus hexataenia (six-line wrasse) would get along in my tank. The LFS says it will work, but I am a little nervous because I have heard that they both establish territories on the live rock.
<Yes, they should... occupy different niches (though both mostly "in the rock"... Have seen these two together in systems many times>
Here are my system specs:
29-30 gal (it's a custom flatback hex that I got as a gift, so I'm not exactly sure of the gallonage, but it is 36" long)
<Hmm, can calculate... by LWH, 231 cubic inches per gallon... maybe use a piece of paper to detail... or by filling with a container of known volume... important information to have at times...>
~25 lbs. of LR
~35 lbs. of aragonite sand (gives me a semi-DSB of 3.5-4")
Magnum 350 for mechanical filtration and circulation
Penguin 550 powerhead (turns over 125 gph)
Brand new Prizm protein skimmer that I am still breaking in Ammonia/nitrite are always 0
Nitrate goes from 15-30 ppm depending on how recently I did a water change (I'm hoping the protein skimmer and the removal of the BioWheel from my Magnum will bring these levels down)
pH 8.2, temp about 79 degrees.
<Yes, should>
Current inhabitants are:
1 C. solandri puffer (3")
2 false Percula clowns (1.5 and 2")
and the lawnmower blenny, who is about 2"
<A bit crowded... keep your eye on the blenny to assure it's not getting too thin>
I've probably given you WAYYYY more information than you'll ever need, but at least you won't have to ask me for more! The wrasse I want to add is 1.5-2". Do you think this would work okay? If anything does go drastically wrong, the LFS will always take fish back from me because I spend so much money in there :). I really appreciate your opinion.
<Hmm, yes, should be fine.>
Please do keep up the good work,
Laura
<I will try my friend. Bob Fenner>

Lawnmower blenny
Hi Bob,
I just added a 4-5 inch lawnmower blenny to my 125G reef. Other tank inhabitants include 2 green Chromis, Naso, Kole, and yellow tangs, Percula, 2 barred gobies, 2 cleaner shrimp, several peppermints and other inverts. My concern is did I just add a potential problem to my tank?
<Unlikely... these Combtooth Blennies are not common prey to these animals or predaceous toward them... almost exclusively feeders on filamentous algae>
He seems ok so far, everyone else did their stare downs. Is it common for these fish to be easily startled or is because it is a new place for him? 
<Yes, and they are just naturally skittish period>
My main concern is will he eat any of my corals or go after the shrimp? 
<Very unlikely>
He seems very peaceful but now the day after I add him I hear that he is not compatible with Kole tangs or he may attack my hand when I have it in the tank. Is there any truth to these accusations or should he continue to be a peaceful addition to my tank? 
<Bizarre. Never heard such things from credible sources>
Thank you much!
Eric Liebe
<Not to worry my friend. Bob Fenner>

Compatibility
I would like to know if a lawnmower blenny would be compatible with my Niger trigger and 2 snowflake eels . Trigger is approx.5 inches and eels roughly 12 to 15 inches in length they are in a 58 gal reef ready I thought I read recently in your column suggesting a blenny was okay with these fish was wanting to use the blenny for natural algae control thanks in advance for your comments and a very informative and educational column
>>
Worth a try with a larger (let's say about 4") individual... these are fast, smart animals... do place it down near the rock when you release it... maybe feed the trigger and eels at about the same time...
Bob Fenner

Goby/blenny
Bob-
Here is more info on my reef tank that you requested so that you could fully reply to my question about blennies/gobies (original question and reply are below).
<Ah, good. Thanks for the info.>
58 gallons with 71 pounds of Manono live rock
1/2 inch layer of aragonite <Grade? I'll assume this is not egg-sand or more than 1/8">
water quality and movement is superior 
2 96w PC
Currently I have 1 Percula clown and a yellow tailed damsel. Ideally I would like to place a Flame Angel, Purple or Desjardin Tang, Banggai Cardinal, Lawnmower Blenny, Neon Goby and a substrate sifter in the form of a blenny or goby. I am concerned that the tank might be over populated with this mix and will be willing to not place the Banggai Cardinal in the tank.
<Leave out the Desjardin's Tang. Too big for this size system>
Other concerns are: I like the lawnmower Blenny for algae purposes and the Neon Goby for parasite purposes. Will the Neon Goby and Lawnmower blenny compete for food resulting in the loss of one? 
<Nope... different foods, niches>
I would like to place a "substrate sifter" but three blennies/gobies seems like too much competition as well. 
<Yes, just one sifter would be best... and the tangs you list will turn the bottom over to an extent>
Maybe I should drop the Neon Goby and buy a Pacific Cleaner Shrimp for the purpose of fighting parasites. Any suggestions?
Thanks a million,
Rob
The Lawnmower should only go in when there is substantial filamentous Green algae (Chlorophyta) to consume... and start with a small specimen... only one. Maybe a Cryptocentrus, Atrosalarias, Amblygobius, Valenciennea species after the system has been up, running a good six months... Suspect we will be "chatting" between now and then...
Bob Fenner

Compatibility
Hello,
I had a question in mind which is troublesome. In my marine reef tank, the ignorant lawnmower blenny keeps on chasing the Hawkfish like it's food. Is the flame Hawkfish able to defend itself, since the blenny is really big. The Hawkfish just keeps on exploring though. They are both breathing extremely quick after a chase and if they don't stop I am going to remove the blenny. Is there any sort of fish that is able to intimidate such large blenny?
<The idea is to have compatible tanks mates, not to find one to be the enforcer.> 
Also, I have a little tomato clownfish ( recently added in) who is extremely feisty. He attempts/ does attack my pair of Sebae or black percula clownfish. However, my purple tang viciously chases off the tomato with his fins, and the pygmy assists in trying to nip at its tail.. Do you think the tang have a bond with the pair?
<No, just defending territory> 
Should I remove the tomato and throw him into my smaller tank and just bring up the pair of false percula clowns instead? 
<Tomatoes are feisty as you say, and the larger they get, the worse it is. I'd see if you could trade him in, or put him in another tank to avoid the problems. James (Salty Dog)>
Thanks for your time! 
<You're welcome> 

Evil Blenny (10/22/04)
Hi, I recently acquired a lawnmower blenny, reading on how they tend to be passive fish. <There is quite a bit of opinion to the contrary. To quote Scott W. Michael's "Marine Fishes" : "Large individuals will attack fish tankmates..."> I had exchanged a very small blue tang for him, since the blue tang drove my clown fish crazy for a month until she couldn't take it anymore, and turned on him.  Before damage was done I returned him, and got a lawnmower blenny.  A few weeks into having him in the main tank, he has decided that he does not like my longhorn cowfish.  The cowfish was the first fish in the tank, and in my opinion, it is his tank.  Now the blenny chases him around, nipping at his belly.  I am worried of stressing out the cow, so I am curious if this is a long-term behavior. <Probably will get worse as it grows. I'd get that blenny out of there before it causes your cowfish to release its toxin and wipe out your tank.> Will it stop after a while, or should I bring him back to the store.  The cowfish is my main concern, and I will do whatever is in his best interest. <Get the blenny out of there.>  I thought if there were going to be any problems, it would be between the blenny and the mandarin I have, since they both tend to hang out by the rocks.  But there are no qualms there.  Any
info would be helpful.  Thanks so much. <Bye, by Blenny. Hope this helps. Steve Allen.>

Re: The Evil Blenny
Hi There,
<Hello>
I saw the post of the person with the evil blenny problem -- attacking his cowfish.  I have no idea how big the person's tank is, but allow me to suggest giving the blenny someone else more suitable to wrangle with.  I have a huge Lawnmower Blenny myself, and he loves to chase a Highfin Blenny.  The other blenny thinks he's nuts, and they just swim around each other.  Just a thought :-
<Thank you for this. Will post alongside the other input for alls edification. Bob Fenner>

The Clownfish and the Blenny (5/25/04)
Hi guys, I had a quick question that I was hoping you could assist me with. I have a 72 gal FOWLR setup. Current inhabitants include a pair of percula clowns, still young about 2 inches, a lawnmower blenny, about 3.5 inches, and 4 turbo snails. I have about 85 lbs of live rock. My problem is that my clowns stay secluded in one corner of the tank. This is the corner they sleep and rest in all the time. <In nature, Clownfish seldom stray from their anemone. they're not particularly adventurous. My Maroon Clown limits itself to maybe 10% of my 180G tank's volume.> Occasionally they will venture to about midway across the tank, but then back to the corner. Recently I observed my blenny acting aggressively towards the clown. <Can be a problem. Lawnmower Blennies can be aggressive.> He swam right up to them and started waving his tail at them furiously. This behavior occurred when the clowns saw me get close to the front of the tank to feed them, and they moved out of their corner. I am afraid that my blenny is keeping them in the corner of the tank. <Probably, but like I said, they often choose an area to stick to.> I have seen this happen a few times thus far. I have read that this particular species of blenny is only aggressive towards conspecifics, and rarely towards other fish. Scott W. Michael specifically states that they can often attack any smaller fish.> Could I possibly have the rare possibility? <Not rare, rather common actually.>
The clowns are in very good health, vibrant colors, fins are not clamped, and breathing normally. Is there any other reason that the fish could be acting this way? <Their natural behavior, especially when threatened. That's why they live in anemones in nature. (But they do not need one in a tank, they need tankmates they can cope with.> I have had the fish in this tank for over a month, which I know is not that long, but they had this corner behavior when housed with the blenny in there previous tank too. The blenny is not as important as my clowns, even though I love his personality. So if he is the problem, then I will find him another suitable home. If so, could you suggest a species of blenny that would not be a problem? A more peaceful species. I sincerely thank you for your help. Brian <If this blenny has been aggressive toward them in to tanks, he is probably an unusually intolerant one. Perhaps he is unhappy because he isn't getting enough food. Does he eat whatever it is your feeding him? Most lawnmower blennies starve because they won' eat anything but hair algae. You could remove him to a QT for a few weeks, re-arrange the tank, let the clowns settle back in and try again. But I'm skeptical given the history of aggression in two tanks. As for alternatives, how about a shrimp goby? Many blennies are territorial and may get aggressive. Blennies to consider are the Midas, Red Sea Mimic and Bicolor. Check out Scott W. Michaels' "Marine Fishes" for ideas and alternatives. Have you considered a Hawkfish? Hope this helps, Steve Allen.>

- Algae Blenny: Clam Nipper? -
I was just about to buy  rock (lawnmower?) blenny when I read that they nip at clam mantles. How true is this? <They occasionally do, most that I've encountered behave themselves. Make sure you supply lots of algae!> Also, will they be aggressive with a yellow headed Jawfish? <Should be fine, Good luck! -Kevin>

Battling Blennies?
I have a 60G reef with mostly SPS corals.  I currently have a pygmy angel (C. Argi) and a blenny with no apparent common name, (Atrosalarias fuscus).
<Both cool fishes, nonetheless! The A. fuscus is one of my favorite fishes! it's been called the "Highfin Blenny" or "Black Sailfin Blenny" in the trade. A great little fish with plenty of personality! mine has been a perfect gentleman for years!>
My local store has both Meiacanthus atrodorsalis and Midas blennies (Ecsenius Midas) both of which are very beautiful fish, and seem to be more active swimmers and likely to spend more time in the water column than my current blenny.
<In all likelihood, yes!>
However, I love my current blenny, and I know there is potential aggression between blennies. Would I be safe to add one of the two species mentioned to my current tank?  I can't seem to find much specific info, but the A. Fuscus is a strict algae eater IME, and the other two appear to be plankton feeders.  Would this work?
<In my opinion and experience, it would! They can be a bit feisty at times, so there is no 100% guarantee, but I feel that it would work for the very reason that you indicate. The fishes inhabit very different niches in the system, and are not likely to compete. I maintain a system with a variety of blennies, and have yet to observe any long-term problems with this arrangement. I'd go for it!>
I appreciate any help. Thanks, Gusty Stambaugh
<Any time, Gusty! Regards, Scott F>

2 Blennies in a 58gal Reef
Hi,
   Just a quick question.  Can a lawnmower blenny be kept in a 58 gal. reef tank with a bicolor blenny or will there be aggression?
<Since they are similar in shape and size I would advise against the mixture of the two species, these species of fish tend to show aggression towards similar shaped fish>
Thanks,<your welcome, IanB>
Erik Jorvig

Blenny, Pseudochromis Compatibility Question 10/16/05
Good Morning
<Same>
I have found much help from this site.  I have researched this question and just would like confirmation on my opinion, please.
<Sure.>
Tank size is 150. If there is an established blenny (lawnmower) in the tank, would he be harassed by a strawberry Pseudochromis added later?
<In such a large tank and with such different species, I doubt it, though you never know with Pseudochromis. I'd chance it.>
Thanks for your time,
<Welcome>
Ellen
<Mike G>

Mixing Multiple Blennies and Gobies 10/11/05
Hello again.
<Hello, Adam J with you this evening.>
I've been searching the site for a while. It has been about 7 weeks since the tank was put up. 100g hexagonal flatback tank ( It's not a traditional hex tank. Dimensions are roughly 60x20x20), protein skimmer, 20 gallon refugium with 4-5" sand, wet/dry.
<Sounds good.>
It's currently stocked with a lemon damsel, 3 blue green chromis, and 2 false percs that was added after the tank was cycled.
<Were they quarantined?>
After the tank adjusts to the clowns I want to add a Redlip or bicolor blenny along with a lawn mower blenny.
<The Lawnmower Blenny Salarias fasciatus can be quite territorial and aggressive towards other blennies. This will be a risk, though your tank size will help it is not a guarantee. Furthermore with algae eating blennies I prefer to wait until the tank is mature to add them, at least 6 months.>
I was just wondering if there will be a problem with adding blenny with blenny.
<Possibly, see above.>
I was also thinking about adding some firefish and a Jawfish or a watchman. Will these fish run into problems with the blennies?
<You should be okay with one of these along with the blennies but all three, these fish all inhabit the same area of the tank and with all of these mixed including the blennies you would likely run into “real-estate” problems.>
Thanks for all the help so far.
<No problem, Adam J.> 

Lawnmower blenny/mandarin  - 1/30/2006
Good afternoon, <Good morning.>
I know that generally the lawnmower blenny and the mandarin are compatible. I have a mandarin currently and would like to get an LM blenny. The problem is that the LM blenny that I am considering buying is 10x larger than the mandarin. Do you think the much larger LM blenny would harm the mandarin?
The other fish in the tank are quite passive and pay little attention to the mandarin, so the new blenny is my only real concern. <The blenny has a peaceful temperament but may be aggressive toward fish with a similar body shape such as the mandarin. You may want to read the FAQ's here from aquarists with similar questions.  http://www.wetwebmedia.com/blencompfaqs.htm
Thank you in advance. <You're welcome.  James (Salty Dog)>
Kelli Duncan

Will algae blenny ruin my tank's "feel"?   6/18/06
Hello -
<Hi there>
quick question for you (lots of writing, but a quick question <g>)...
I have a roughly 60 gallon tank that someone built for themselves before selling it to me on eBay.  It is 36"x24"x18", so it has more "horizontal surface" in the tank than a "standard" 60 gallon (perhaps an important fact given the fish involved, perhaps not).
<Yes>
There is roughly 65 lbs of live rock in the tank (arranged to provide lots of interesting channels, caves, and resting spots for the critters listed below), a 4" deep sand bed, and a home made sump/refugium that holds approximately 10 gallons of water (5 of it in the refugium section where bubble Caulerpa and Chaetomorpha are working away).  I am also running an EV-120 protein skimmer, and a 4" crocea clam in the main tank helps process the water as well.
<Neat>
My plan from the beginning has been to go with all small fish, including several "rock sitters" that tank observers will only notice AFTER they've been looking at the corals (mostly SPS and LPS) for awhile and then see the fish suddenly dart from one spot to another.
Current fish/shrimp line-up:
2 percula clowns*
2 purple firefish
1 Rainford's goby (eats a variety of frozen and flake foods in addition to tank critters so he doesn't seem to be starving (knock on wood)!)
1 red head goby (Elac. punct.)
4 green banded gobies (Elac. mult.)
2 peppermint shrimp
2 cleaner shrimp
Down the road, I am hoping to add one of the colorful mandarin "gobies" (Synchiropus) as well.
My question is:
In a separate 12 gallon tank, I have a 3.5" algae blenny that my wife and daughter would like to see in the big tank in the living room rather than the little tank in my office.  I, too, think it would be nice to have the fish in a more visible place, but I have the following concern:
I have read in a number of places that they sometimes become fairly territorial, and I would hate for all my gobies to wind up spending most of their time in hiding rather than flitting about as they do now.  If the algae blennies only get territorial towards fish with similar body shapes, perhaps I am ok for now... but when I add the mandarin, it will be the most "similar" fish in the tank, and I'd rather have the mandarin (and the rest of the gobies) than the algae blenny if the WWM Gods declare "thou shall not even think of adding the blenny, Nate."  Would you recommend adding the algae blenny? Not a problem? a huge problem?  or is it truly one of those 50-50 toss- ups dependent on the fish's own personality?
Thanks in advance!
Nate
<Mmm, I share your concern (enough) Nate that I would not place this Salarias/Atrosalarias blenny. Too likely as you state to negatively interact with what you have established, hope to add. Bob Fenner>
* well, I haven't actually counted the spines, but I am thinking probably one true and one false percula, though my LFS sold it to me as "true" when I first got into the hobby.  Anyhow, I bring it up to add to the collective pool of "captive clownfish lore"... the true percula is a fairly recent addition to the tank, and it came from the wild, whereas the first one was definitely tank raised.  Though it has not fully adopted my branching hammer coral yet (as I have read they sometimes do in captivity, even though they would not in the  
wild), the wild percula is definitely spending a lot of time hanging out right on the edge of the hammer coral - and actually seems to be trying to show the other one "how to chill with the coral" as well...   the old one doesn't seem too interested yet, but the new one definitely is getting closer and closer to swimming "in" the coral every day!  pretty neat!
<I'll say!>

Lawnmower Blenny with Expensive Appetites - 10/15/06
Lawnmower blenny... just a note for you guys to add to your site. I recently purchased a healthy lawnmower blenny ..approx 4 inches. I had read on MarineCenter.com in a small excerpt that marine center had heard that a lawnmower blenny may nip at stony corals but they had not seen it. Well, maybe the risk is minimal but I had a beautiful multi color polyp coral... HAD is the key word... I wasn't sure why the coral was eroding away but watched the tank carefully and saw the blenny rip several pieces of the polyp from the rock base in no time. Needless to say, and in my opinion, the lawnmower blenny is a serious risk to anyone who has stony corals... believe me... I know first hand. Have you heard or seen this behavior with the Lawnmower Blenny???
Brad S.
New Jersey
<Brad, thanks for sharing. I will quickly say that I'm not surprised - there is always variation among individuals. These types of issues are what fuel the fires of things like the "Reef Safe Angel" and similar fish who are or aren't supposed to eat things they end up eating. All I can say is that an aquarium is artifice - there is no way to ever completely duplicate a 100% natural environment so that these fish end up doing things they wouldn't normally do. All we can do is document it and hope it helps a future aquarist. Thanks again for sharing.
Cheers, J -- >

... Lawnmower Blennies... comp. Poor English  07/21/06
hi there. I have a 30 gallon reef aquarium with a lot of algae. I also have a yellow tang and a spotted watchman goby. can I add a lawnmower blenny?
<<Mas:  Lawnmower Blennies have been known to be finicky eaters and could easily run out of food in your 30 gallon tank.  In which case, you would have to feed Nori on a clip.  Additionally, they can get quite big (4 inches or more long).  Given that the Yellow Tang is also an algae eater, you should pass until you have a bigger tank.  Best of luck,  Roy>>

Lawnmower blenny biting my tangs  12/12/06
<Hey Kathryn, JustinN here tonight>
I have a 75 gallon tank with a yellow, a scopas, a regal, a purple, and a sailfin tangs, two clowns, a royal Gramma, a rock crab, a hermit crab, a couple urchins, 2 small conchs, and a lawnmower blenny.
<...You're...not.. kidding..? You are incredibly overstocked. Your Regal, Sailfin, and Scopas tangs will all MASSIVELY overgrow this tank, can all get upwards of a foot long! Regardless of this, this is simply too many tangs, even for a tank twice this size! You are physically, and psychologically, overcrowded.>
The blenny has only been in the tank for about 2 months. He is 2-3 inches long. My tangs are all 4-5 inches. Lately the lawnmower blenny has been bumping the tangs with his mouth as they swim by him. It appears that he has actually injured the sailfin tang on both of his sides.
<Likely a retaliatory attack, due to aggression you are simply not seeing.>
Is it possible that the blenny is so hungry that he is going after anything? I feed dried seaweed on a clip, frozen brine shrimp, frozen emerald, and pellets. My tank had lots of algae, however it is running low (maybe why the blenny is getting aggressive?) Any suggestions?
<My suggestions: Get rid of the 3 aforementioned tangs! Soon! Things should calm down after such. Hope this helps! -JustinN>

Blenny mixing  11/12/06
Hello,
   I have a 65 gallon reef tank, I was wondering if I can add lawnmower blennies in with my black sailfin blennies?    Thanks-Sue
<Mmm, a Salarias species might well fight with any other bottom dwelling fish... I would skip this mix. Bob Fenner>

Lawnmower Blenny With A Taste For Cloves – 4/7/07
Hi,
<Hi there!>
I was wondering if you could help...<Sure hope so!> last week I purchased a lawnmower blenny. <Love ‘em!> I have closely been watching his behavior and have noticed he enjoys chewing on my clove coral <Uh oh>. After speaking to my local fish store, they advised moving the coral but could not advise further. Is this normal behavior and is there anything I can do to salvage my coral without getting rid of my blenny?? <I’ve read reports of these fish occasionally nipping at corals but after watching mine, and knowing what big appetites these fish have, I wonder if they aren’t actually going after bits of algae or tiny invertebrates in amongst the polyps. Although Lawnmower blennies are predominantly herbivorous, mine will go after any pods it spots around the tank. You might try supplementing your blenny’s diet with Nori, or sinking algae wafers. Hopefully, he'll decide that he prefers the readily available food and leave your clove polyps alone!>  
Thanks
Michelle <You’re welcome and good luck! –Lynn>