What should I do about my Comet/Roundhead that has a lump in its throat  - 03/09/2006
Dear Reefers,
<Okay>
I have a successful (with your help) 4 foot LPS reef tank with 3 fish. It was set up in August 2003, is a natural skimmerless tank, with 3.5 inch DSB, ample LR and a reverse lit Caulerpa sump. As far as I am aware all parameters are ideal.
The first fish introduced in April 2004 was a Comet ( C. altivelis) . It started at 3 inches and is now approximately 6 inches long.
In September 2005 I introduced a One Spot Fox Face (Siganus unimaculatus) in order to control Caulerpa and other algae in the main tank, which it has done superbly. Since then the Siganus has grown considerably and is now larger than the Comet. The Siganus has venomous spines (lots!) but as far as I know there are no other venomous inhabitants. The only other fish is a harmless little Kole Tang.
The problem arose on 29 December 2005, when the Comet appeared unsettled and would not eat. Up until then it had fed every day. The next day it was hiding behind the rocks and did not come out at all for 5 days until 3 January 2006. It was breathing heavily, with its mouth permanently gaping. It also had a noticeable lump on its throat.
<Good observation>
Ever since then the Comet has remained in this apparently distressed state, and it appears that the lump is growing - it is larger than a pea. The Comet now only eats every 2 or 3 days, and its mouth is in a permanent gape. The other fish, corals, snails and hermit are all fine.
I originally thought that the Comet had rammed the Siganus and been caught by one of its venomous spines. If so, would this not have cleared up by now?
<Likely so, yes>
Could it be that the Comet swallowed a Cerith snail or a crab and still has this stuck in its throat?
<Possibly>
If the lump is a cancerous growth, why did it appear to happen almost overnight?
<... Another not-too unlikely possibility is a thyroid (actually diffuse Chromaffin tissues in fishes) anomaly... analogous to "goiter" in humans... From a deficiency (or surprisingly from an overdose) of iodine/ide... Do you dose Lugol's? Do you test for?>
Please help me decide what to do now.
How long do Comets normally expect to live in captivity? Is the Comet likely to recover?
<Can live several years, can recover>
Should I carry on feeding it until it dies naturally, or should I attempt to intervene and apply euthanasia? If so, is there a recommended method for fish of this size?
Many thanks,
Best wishes from the UK,
Eric Brightwell
<I would soak some of the types of foods this animal is feeding on in an iodide prep. prior to offering. Bob Fenner>

Marine Betta   1/31/06
Hello, WWM crew! <Hi Rebecca>
I recently acquired a marine Betta for my 165 gallon reef tank, the smallest one I've seen in any LFS (but not that I've seen too many-they seem to be common and rare at the same time.) It's about 4 inches long total, so you know that means about 2-2 1/2 inches of body. I know it will eat invertebrates, but so far it
has left the fire shrimp <Not for long.> and the hermit crabs alone-I think the shrimp is too big for it. <Will soon change.> I tried to make it
eat frozen food thought starvation, but it hasn't worked. I probably didn't try hard enough. I didn't really leave him in hunger for that long-a couple days at a time. I had read a site that said to feed saltwater tolerant feeder fish, like mollies or guppies, until you can get it to eat prepared food. I
realized, hey, why not just feed it guppies continuously since I've for a continuous supply? I have a 30 gallon freshwater tank filled to the brim with guppies in various stages of growth. (I started out with 5-2 female and 3 male.) So I tossed several babies in, after acclimating to saltwater. They were immediately eaten by the other fish, mainly the Chromises. So I tried again later, dumping the baby guppies with one hand while dropping in flake food at the other end of the tank. I don't know if you've ever seen a marine Betta hunt, but it is really neat. It kind of curls it's body around, so it's prey is confused by the eyespot, and it herds the fish into a corner so it can nab it. Anyways, my questions are, since I do have a continuous supply of guppies, is it okay to just keep feeding them to the Betta? Do I really need to acclimate them to saltwater first every time? <No, they probably won't last that long.>I've been just tossing them in one at a time, they don't last long enough to be too stressed out by the changes in temp and salinity. Plus it has other things to be stressed out about ;) How many should I feed per day? <Rebecca, it's OK to feed guppies/mollies as an acclimation food as the marine Bettas can be somewhat difficult to acclimate as far as feeding.  Once he has his appetite back, gradually introduced prepared foods (frozen variety).  Feedings of two to four times weekly are sufficient.  Hard to tell how many guppies to feed per feeding not knowing size etc.  Like any other food, feed until he no longer shows interest.  The Betta, once acclimated is hardy and disease resistant.  Do provide hiding places for him as in nature they are nocturnal and will need to get out of the lights from time to time.>
Should I have the guppies soak in anything in particular first that would give more nutrition to the
Betta? <Could feed the guppies brine shrimp soaked in Selcon or similar vitamin.> Do I have any more questions? Hmm...Nah, unless
you can tell me how I get the Betta to pose for me so I can take a picture. <Tell him to say "cheese".>
Thanks! <You're welcome.  James (Salty Dog)>
Rebecca

Marine Bettas  11/21/05
Hi Team
<Tim>
Quick question about marine Bettas (Calloplesiops altivelis).
<Neat animal>
I have found information regarding these on your site and advanced aquarist.  They say after spawning it takes about 5 - 6 days to hatch. They hatch out at about 3cm long. What would you feed these guys? Enriched brine shrimp, I
<I>
assume rotifers would be to small?
<Agreed>
Also do you have any other insights as to how to tell male and female?
<No>
I have noticed on the two I have (different tanks) the smaller one has finer white dots and more of them compared to the larger which has bigger dots, and not so many of them.  Could this be a way of sexing them or could it be more likely that they came from two different areas?
<I don't know>
Also, do you have any good links about breeding them?
<Mmm, just the one piece that was posted in Aquarium System's "SeaScope" a few years back... I would "hit the stacks" at a large library re this, other citations. Bob Fenner>
Thanks for the help.  Tim 

Query about Comet fish (Marine Betta) 8/5/05
Hello,
<<Hello George - Ted here>>
I am an Australian marine tank enthusiast with a 5x2x2 foot tank about 1 1/2 years old. I was told by my local aquarium supplier that WetWebMedia was an ideal site to perhaps find out some answers to my questions about introducing a second Comet fish (Marine Betta) into the tank.
I trawled through some of your FAQ's, but couldn't find the answers, or indeed any bold references to Bettas, despite the Google search results listing some encouraging sounding references. So I'm contacting you directly to see if you can steer me in the right direction. I'm happy to pay a subscription fee if you'd like, but I wanted to first find out whether you'd be able to help me.
My questions are as follows:
Would the new Betta fight with the one that's been in the tank (albeit as a bit of a recluse) for the last 6 months?<<Marine Betta's are found singly, in pairs and in small aggregations in the wild so adding a second one is a possibility. Particular individuals may or may not get along. While fighting could be a concern, I would be more concerned with the ability of your tank to support the food needs of two Betta's? Betta's can be finicky eaters. Is the second fish already eating frozen or prepared foods? Is the established fish eating frozen or prepared foods? The population of pods and other infauna in your system may support one fish but may not support two.>>
Would introducing a second one encourage the first to be less of a recluse perhaps? Is the sex of the fish important, and how would I ascertain the sexes of both the existing fish and the proposed new one?<<Betta's are reclusive and the introduction of another will not end the reclusive behavior. Dim lighting may induce less reclusive behavior. With time, some Betta's become less reclusive. Betta's have been successfully bred in captivity but sexing them is difficult. They may be hermaphroditic so that placing a large and small Betta together might increase the chance of getting a pair.>>
I hope you can respond quickly, as the offer to accept the second Betta won't last long.
Best regards
<<Cheers - Ted>>
George Lewin
Byron Bay
Australia

Re: Query about Comet fish (Marine Betta) 8/9/05
Hello Ted (and the rest of the WWM FAQ crew) for your prompt reply to my questions.
<<Hello George and you're welcome>>
I'd love to send you a donation, and will do so as soon as I've written this email, to help you keep up the good work.
<<Thank you!>>
Before making a decision on the second Betta, I plan to discuss your comments with my local aquarium supplier as soon as he returns from a few days off.
In the meantime, does anyone there have any idea about what the worst case scenario might be if I introduce the second Betta - who I believe lives on frozen and prepared food, as does my current tank inhabitant.
<<Both eating frozen and prepared food is promising.>>
If there's insufficient food for both, am I likely to have two starved Bettas, or will Darwinism triumph? Or perhaps I should start introducing live brine shrimp and/or mosquito larvae as a means of fattening them both up, at least in the short term?
<<You should quarantine the 2nd Betta (as you should all new arrivals). Use the quarantine time to fatten both Bettas up. When you place the 2nd Betta into the system, if either should succumb, you will have eliminated disease as the culprit and verified that the new arrival is eating before introduction to the main system.>>
Fishing out a dead Betta would probably be quite tricky given the number of caves and hidey-holes in my live rock assembly.
<<You can't be certain with individuals from any species, but knowing that you have started with two healthy, eating fish will go a long way towards success. With any luck, you won't be hunting for any missing fish>>
Best regards
George Lewin
<<Good luck - Ted>>

Fish compatibility 3/11/05
Thank for the advice. I hear conflicting stories of the Marine Betta (comet).
<they are generally well-behaved with anything they cannot swallow whole>
He doesn't pay attention to the two smaller fish [right now] but like I said I am selling him back to the pet store as soon as I can get him out without causing chaos.
<they really are some of the best and hardiest fishes for aquarium use... wonderful fish>
He is really cool but not worth it. So now I just need to decide between clowns and wrasses! thanks Kim
<all good... Anthony>

Marine Betta Buddies...
Hi Guys
<Scott F. your guy tonight>
I am living in Bangkok, Thailand.  Previously Australia.  I have just set up my 270ltr (65 gallon) reef tank - about a month old.  Wow.. So much trouble to get reliable service and equipment here. I know it's early days but after learning some lessons setting my first reef tank up, I am planning well ahead to avoid the same mistakes. So I am seeking some advice in advance of stocking when the tank is ready.
<Glad to help>
The tank has no sump,  two Rio 3000 powerheads with split duckbill adaptors to direct the current, a Red Sea hang on Berlin venturi skimmer (noisy pump on that model - I don't recommend one - can u suggest a quiet pump to drive it), a canister filter will be fitted to filter for phosphate/nitrate removal, 2 x actinic 30watt and 2 x Clear marine fluorescent tubes that came with the tank Should I change them to 40 watts - the light seems to dim to me),
<The more light the better, in most applications>
a Resun CL-280 chiller (really efficient and super quiet, low heat output!).  About 1/3 of the tanks is taken up by the live rock reef which has lots of caves, good current flow and the base is crushed coral (the only reliable stuff  for a base you can get here).
It's to be a coral tank mostly (soft and hard corals).
<I think that your corals will fare better in the long run if you stick to one or the other (soft vs. hard corals).>
Recently I saw a marine Betta (Calloplesiops altivelis) in a store here which the sale guy recommended as placid and reef friendly  (people here will tell you anything for a sale, so I am not sure to trust this).  Are they ok in a reef, what are some ok tankmates and a clean-up crew to house with them.
<They will not harm sessile invertebrates. However, they will prey on small fish, if they can catch 'em. I have had one in my reef tank for some time, and he seems too slow to catch many of the small blennies and gobies that I keep, but I wouldn't put it past him. Also, being a secretive fish, you might only occasionally get a view of him, but it is always a spectacular sight when he emerges!>
I was planning to  slowly stock the tank with a maximum of 6 to 8 fish.  1 feature fish (maybe the Betta)  to not exceed 6 inch and the rest about 2-3 inch max.  Is this too many  and are the smaller fish going to be in danger from a sea Betta?  Your Sincerely, Brett
<As above. The Marine Betta can get pretty large (like 5 inches or so), when it can become a realistic threat to small fishes. However, most of the medium sized wrasses, Pseudochromis, etc. could be okay, as long as sufficient hiding places are provided. I'd draw the line at about 4 fishes, plus the Betta. Yes, it's a bit conservative, but I think it will serve you (and the fishes) better in the long run. Good luck, Brett! Regards, Scott F.>

Unfriendly Competition? 
Hello folks, 
<Hi there! Scott F. with you today!> 
Does anyone have any idea if a Paraplesiops poweri will get along with a Calloplesiops altivelis? I have a 92g corner bow front with a lot of rock work. In there currently are 2 percula clowns, a small Hawkfish, a finger dragonet and a very small cow fish. Thanks. Tim 
<Well, Tim- as you know, these fishes are similar in both habits and basic appearance. If it were me, I'd be hesitant to recommend keeping them in anything under a 6 foot long tank. Although both are relatively shy, they are predators, and require a certain amount of space and territory to be at their best. I would not label them as "gregarious" by any means, so I'd pass. They are possible competitors, and this is a good enough reason to avoid mixing them, in my opinion. Hope this helps! Regards, Scott F>

Marine Betta
Hi,
Would a marine Betta be compatible with invertebrates,<nope.. they are closely
related to groupers and behave like them...that means they will eat shrimp/crabs etc> and live happily with a potters angelfish, regal tang, and 2 ocellaris clownfish.<If the Betta is big.. then I would not house him with clownfish.. if he is small then you might be ok> If it would, could I be able to keep it until it gets fully grown, or will I have to get rid of it? <I believe they grow to about 6"...you should be able to keep this fish through adulthood in a regular 55gallon aquarium (hopefully you have an aquarium at least this size, good luck, IanB>
Regards Daniel...

Multiple Assessors - 8/13/03
Hello again-
<hello... just called... to say... Hello [Neil Diamond loves us all]>
Your site and advice is always outstanding!
<we are all farmers indeed... out standing in a field>
I have read conflicting advice on this and wanted to get a direct answer. I am thinking about adding 2 or 3 more blue assessors to one already in my 110 gal. Perhaps yellow instead. Will I have a problem ?
<what few aquarium reports I've seen, these fishes are pegged at 100 gallon tanks with a lot of rockwork as being minimums for a chance at a shoal. The blue assessor is believed to be slightly better behaved in groups>
Also is there a way to tell male from female? Much thanks as always.
<none that I know of... read more here (follow various links on the page):
http://www.fishbase.org/Summary/SpeciesSummary.cfm?ID=14960&genusname=Assessor&speciesname=flavissimus
http://www.fishbase.org/Summary/SpeciesSummary.cfm?ID=12827&genusname=Assessor&speciesname=macneilli
Anthony>

- Mating Habits of Assessor flavissimus -
I have been looking all over the place for information on the mating process of the Yellow Assessor (Assessor flavissimus). <Lovely little fish.> I have 3 of them and 2 look to be fighting, I was unsure if this was to gain access to the female or if it was a mating dance of some kind. <I'd be willing to bet that those are your two males, and one is working to establish dominance over the other, and likewise access to the female.>  Here is a link to some pictures I do have more if so need them.
http://home.comcast.net/~kc1891/wsb/html/view.cgi-photo.html--delay-5-SiteID-761324.html
Let me know what you think. <Neat slide show - most certainly some aggression there. I'd consider removing the one that looks to be the weaker of the two, before it succumbs.>
Thank you in advance,  Keith
<Cheers, J -- >

- Assessor flavissimus Aggression -
First of all I would love to remove one of them I would hate to see one die! The hard part is removing it, it has been several days since I took those pictures and they seem have clamed down not fighting near as much. <Well... just keep an eye on things. If the aggression steps up, you'll have to do something.> Is there any chance they will be able to live peacefully? <There's always a chance.> Do you think I have a good chance at mating these fish if so what do you think it would take? <Do know that the males are mouth brooders, but I don't know enough about the spawning habits of these fish or the needs of the larvae.> I hope to be moving them into a larger tank in a few months (60G to a 120G) do think it would be alright to add more to a 120. <If you want these to spawn, you'll need probably to leave them by themselves.> I am really not sure if they are like Chromis where if you only have a few of them they fight but if you have a large grouping the do much better? <I've not heard this about these fish, but am pretty sure they are found in groups in the wild.> Any ideas well be great.
Thanks for your quick reply,
Keith
<Cheers, J -- >

Assessor flavissimus observation
Hi, all,
This isn't a question, just an observation on my yellow assessor (Assessor flavissimus). I had him in a fairly quiet tank (2 A. ocellaris who never leave their anemone), a Halichoeres leucurus(?), scooter mandarin. He only came out to eat but otherwise I never saw him. I added a trio of bar gobies (Ptereleotris zebra) and he suddenly started appearing all over the tank. At first I thought the gobies had scared him out of his lair but now it appears (to me) that he just likes having other fish in midwater. He seems pretty happy and there are no obvious signs of stress or aggression. Based on that, it would seem they do best with other free swimming fish.
Anyway, since there isn't too much on Assessors in the WetWebMedia FAQ, I thought I'd toss that out. They are a nice peaceful fish for the right tank. For aesthetes in the crowd, the yellow assessor is not the brilliant yellow of many tangs or butterflies but it is fun to watch. While I'm at it, I tried one of the blue Assessors some time ago. It seemed to do fine but judging by its behavior (only out in dim light, before tank lights on and damn hard to see even with the lights on against a black background), I can't really recommend them unless you happen to like fish
you can't see ;-)
Marc

Roundhead addition
Hey Crew,
Last night I was at a local fish store and spotted the most unique looking "Grouper" that they were selling for $20.00.  Little guy caught my eye so after talking to an associate about his needs I picked him up to go into my 54 corner.
Well.....  After doing a little research it looks like I have a Marine Betta on my hands.  He is black with white spots and has the (eye) near him top dorsal fin.
I am a little surprised at the mistake from the store but now I am unsure of the needs of this fish.
What do they eat?  Temperature?  Cover?  Tank mates?  Lighting?
My tank is mostly a reef setting with lots on live rock and plenty of inverts.
Any advise as to how to give this guy a good and happy home?
<Please read here: http://www.wetwebmedia.com/roundheads.htm and the FAQs (in blue, at top) beyond. Bob Fenner>
Thanks in advance,
Michael Bukosky

Assessor macneilli
Hey everyone hope all is well!  Quick fish question for you.
<I'm doing fantastic! If only I didn't have to go to work tomorrow...<sigh>
I am looking for some information regarding the Assessor macneilli but it seems hard to come by.  The only reference to it I could find on WWM was a picture and one person mentioned it in a FAQ as part of his livestock list.  Also there is no specific/detailed mention of it in Bob's CMA or Dr. Burgess's compendium of aquarium fishes.  Since I am unable to find any good references for this fish I am reluctant to purchase.  So far I have found that it tends to grow to a maximum of about 3" and that it is omnivorous and supposedly "reef safe" (we all know what a misnomer that can sometimes be).  I believe it is also considered a Basslet.  
<Max. length is 2.4". Likes meaty foods, is reef safe, very hardy and suitable to aquarium life, can keep singly or with a group (use one larger fish and 3 or 4 smaller fish and add all at the same time), also not very aggressive. Ideal for quiet community tanks>
Current inhabitants of my tank are:
Various snails
2 or 3 hermits
1 T. squamosa
1 Entacmaea quadricolor
1 Premnas biaculeatus
1 Pseudocheilinus hexataenia
It was the last bit of livestock I wanted to add to my clam/anemone only tank, along with maybe a few more snails from the Nassarius family.  
<I think this fish will work out fine for your situation>
Thank you in advance for any advice!
<You're more than welcome! David Dowless>
RVM

Marine Betta
Was offered a Marine Betta-----I have a 55 gal. tank, occupied by sm. tang, two med. clown fish. Will they be ok together?  ( Betta is about 8",s )  
<Your tank is a bit too small... the Clowns might go after the Betta... I give you about 50:50 odds (if there's a large enough rock cave for the newcomer), but about 100% if the system was more than one hundred gallons. Bob Fenner>

Marine Betta
Mr. Fenner,
I work at a pet store and about a month ago we got a box shipped to our store that we did not order. One of the fish that was inside was a marine Betta. After a bit of begging the manager let me take him home to my 125 gallon reef. He is an incredibly shy guy but if I turn the lights out in the room and sit for a bit he comes out and displays in front of the glass for me rather nicely. The problem is that even though he looks great and hasn't lost a bit of weight I haven't seen him eat at all. I have about 150 lbs of live rock that I have had for three years and I was wondering if maybe he has been finding stuff off of that to eat. If you could give me some kind of feeding information on these fish I would appreciate it greatly.
<Since he is so shy, start him off with some gut loaded live foods, such as ghost shrimp. Then wean him onto other foods, like frozen krill and eventually prepared Formula-types. Look at the WWM site for info on training groupers and lionfish to eat prepared foods. A varied diet is best. -Steven Pro>