BrackishDailyFAQs

Updated 5/12/12
Other Specialized Daily FAQs Blogs: General, Freshwater
Daily Q&A replies/input from the WWM crew: Neale Monks, Marco Lichtenberger, Eric Russell, Chuck Rambo, Bob Fenner, are posted here. Moved about, re-organized into individual FAQs files!

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GSP, sys. 5/6/12
Hello!!
<Hello Jordan,>
I couldn't find a clear answer to this, so I was just wondering if I could keep a Green Spotted Puffer in a brackish water aquarium with a specific gravity of 1.008 it's whole life.
<Yes.>
Or do I have to increase the salinity as it matures?
<No. Many people do keep them in marine-salinity aquaria for various reasons. GSPs seem to get along with robust Damselfish, for example. But this is strictly an optional thing, and not essential. They can and will live healthy lives from SG 1.005 upwards provided water quality is good (0 ammonia and nitrite, <20 mg/l nitrate) and the water chemistry is correct (15+ degrees dH, pH 7.5-8).>
Thank you :)
<Most welcome. Neale.>

RES and Dragonfish Together as well as health problem 4/27/12
Hello, My names Nicole.
<Hello,>
I am writing you all for 2 reasons. First is I have a baby RES and today my lovely Boyfriend brought home a small Dragonfish and put it in our 50gal tank with Mr. Turtle. (I know very original name) Can the 2 of them survive okay together?
<No. The "Dragonfish" is, I assume, a Dragon Goby:
http://www.wetwebmedia.com/ca/volume_3/cav3i3/Dragon_Gobies/DragonGobiesart.htm
These big, ugly but very good fun fish are brackish to seawater animals and cannot live for long in freshwater (despite some of the more unhelpful retailers selling them as freshwater fish). If you add enough marine aquarium salt mix to the water for this fish (between 5-10 grammes per litre) you'll severely stress, perhaps kill, the turtle. On top of this, Turtles and Fish DO NOT GO TOGETHER! Turtles make so much mess (urine, faeces) that water quality in their tanks gets very bad, very quickly.>
Second is I noticed that my RES' shell is soft. I had no idea because he seems normal, very active.
<Poor diet; lack of calcium; no UV-B lamp for him to bask under.>
Only problem is I have had him for a month now and still have yet to see him eat. I have used pellets, dried shrimp, freeze dried blood worms.
Calcium supplements for the water and UVB light. What else can I do.
<Read. Start here:
http://www.wetwebmedia.com/fwsubwebindex/RESCareBarton.htm
>
I have "Googled" and cannot seem to find anything that I have not tired.
Please help. :)
<Hope this helps. Cheers, Neale.>

Goby Dragon tank question. 4/27/12
HI,
I've been reading through your site, and am most impressed. You've amassed an amazing amount of information here.
I've read dozens of articles which have drip fed me bits of information, but I'm having a difficult time applying all that I've learned to my current situation.
Whilst I was away for a few days working, a well-meaning grandparent took the resident 5 year old to the 'fish store' .. and they came home with a Goby Dragon (Gobioides broussonetti I believe). It was in the tank for a week before I came home and saw it.
I'm now struggling to do my best to give this fish as long/healthy a life as possible.
<Good>
For a bit of background, we've got two tanks, one 45 litre, the other 110 litre. Both are freshwater (Yes, I've read that the Goby needs brackish water).
Having done my reading now, it appears that the two tanks, if put together, would be far too small for the Goby to be happy/healthy in, so I've purchased another tank, listed as being 90 gallon, which I'm setting up for the Goby as soon as we complete our move (in the next 2 months.).
The tanks we do have been stable for 2+ years, I test the water weekly and the water quality is excellent.
<Hard, alkaline tending I take it>
I do a 30% water change on both tanks weekly, and this has seemed to work very well for me so far. I've lost no fish at all for > 1 year, and as far as I know, the tanks are completely disease free. Both tanks have two filters, which combined are rated for about double the volume of the respected tanks.
In the meantime, given that I've got two fairly small tanks, is there way that I can convert one tank to brackish?.
<Sure...>
I've been looking online to find which of the fish we have could be healthy in brackish water, and I'm not finding a huge amount of info regarding..
<You can look them up as individual species on Fishbase.org (a reliable source) and read what sorts of water/habitat they occur in naturally>
We've got a couple of Plecos, two kissing gourami, a red tail shark, a few harlequins, two 'ghost cats', and two elephant fish.
<Mmm, of these, only the Helostoma will really tolerate much salt content>
Would any of these fish be ok in the smaller tank if, for the 2 months before the move, I converted it to brackish for the Goby?
<Depending on the sizes of all... I'd place the Goby in the smaller... add salt (marine) to more brackish slowly...>
I went to the back to where they bought the Goby, and he insisted that these have now, for many generations been bred and raised as freshwater,
<News to me... as far as I'm aware, this species is all wild-collected>
and that to introduce him to a brackish tank would be likely to stress/kill him. --
This is contrary to EVERYTHING I can read about the fish.
<Me too>
Given the situation I'm in. Any suggestions at all as to what might be best to do?
<As stated above...>
to move all the other fish from the small tank to the large would over populate the large tank to an unhealthy degree.. and would still leave me with the Goby in a small 45 litre tank.. but would that be the least stressful option for the fish until we're moved and the new tank is setup?
<As we both state... if the goby is under six inches, 15 cm., not likely a problem for a couple months>
I know it's a bit of a nightmare situation -- it's not one I would have created myself.
As the 5 year old ADORES this Goby, I'd very much like to not have to get rid of it but I don't want to keep it in a compromised set of conditions which would see it suffer or lead a shortened life.
Thanks in advance for ANY assistance you might be able to give.
Regards.
<And you, Bob Fenner>
Re: Goby Dragon tank question. 4/27/12
<<Would add that Dragon Gobies need higher salinity than even Kissing Gouramis will tolerate. Think of Dragon Gobies as marine fish that happen to tolerate freshwater for a while. In any case, do read here:
http://www.wetwebmedia.com/ca/volume_3/cav3i3/Dragon_Gobies/DragonGobiesart.htm
Lots of salt-tolerant tankmates do really well with them; really, anything that won't compete for food and won't nip at their fins. Guppies are a great choice, and surprisingly perhaps, the adult Dragon Gobies won't even eat newborn Guppy fry! And yes, as Bob pointed out, all these fish are wild-caught, and your retailer telling you they are bred on farms was either "feeding you a line" or ignorant of the facts. Cheers, Neale.>>
Re: Goby Dragon tank question. 5/1/12
Hi,
Thanks so much for your quick reply. Unfortunately the little bugger is about 315mm long at the moment. So the 45 litre tank is really minimal for him.
Although I was going to wait until at the new house to set up the larger tank, I think I'll do some shuffling around and get him into the 110 litre which I've had offered on loan from a friend. At least in that, he'll have a bit of room to move around and I'll be able to give him the brackish environment he's looking for.
I've never done any of the 'quick start' type methods for getting a tank to mature as quickly as possible. Aside from moving an existing matured filter
and as much water over as possible from existing the existing tanks, Are there any viable shortcuts I can take to minimize the amount of time that the 110 litre brackish tank would take to be ready for the Goby to go in?
<What you list... the use of a commercial product, the movement of mulm, substrate, filter media... converting to brackish (adding salt) slowly,
over week's time>
I've read repeatedly that these fish must be put into a matured tank and I don't want to at all stress him further with any of the tank cycling process.
Thanks again for your assistance and replies. They're much appreciated.
MG
<Welcome. BobF>

Dragon Goby Stuck in Cave /RMF 4/22/12
Hi, my name is Susan. I have a BW tank for my dragon goby. He is about 14" long and pretty thick. We also have hollow rocks that make great caves, especially when the dragon goby was smaller. Well I was gathering up some mollies to move them to another tank and I think I spooked the dragon goby.
When he didn't come out to eat, I searched the tank and found him squished inside a rock. He is not coming out and feels pretty packed in there. I can break the rock since its ceramic, but I don't want to hurt him in the process.
I also thought these fish might be air breathers and I'm thinking he is probably dead. Is there a way to break the rock without hurting him?
Should I break the rock? Thank you very much for your time. You guys have a great website and do a great service to the fish keeping community.
Susan

Dragon Goby Stuck in Cave /Neale 4/22/12
Hi, my name is Susan.
<Hello, Susan!>
I have a BW tank for my dragon goby. He is about 14" long and pretty thick. We also have hollow rocks that make great caves, especially when the dragon goby was smaller. Well I was gathering up some mollies to move them to another tank and I think I spooked the dragon goby. When he didn't come out to eat, I searched the tank and found him squished inside a rock. He is not coming out and feels pretty packed in there. I can break the rock since its ceramic, but I don't want to hurt him in the process.

I also thought these fish might be air breathers and I'm thinking he is probably dead.
<Hmm… wouldn't bank on it just yet. These fish are normally quite resilient.>
Is there a way to break the rock without hurting him?
<Yes, assuming this is ceramic or lava rock rather than a tough rock like limestone. Put the object on a wet towel. Tap firmly with a hammer. Hopefully he'll slither out before the thing actually breaks, but ceramic is pretty brittle and should break with little harm to the enclosed fish. If actually rock, then things become riskier. I'd wait a 3-4 hours, but if he's still in there, I'd do as above, but carefully.>
Should I break the rock? Thank you very much for your time. You guys have a great website and do a great service to the fish keeping community.
Susan
<Good luck, Neale.>
Re: Dragon Goby Stuck in Cave 4/22/12

<<Ah, you see I thought to break the ceramic outside of the water… easier to be careful and less concussive force transmitted through air than water, so less shock to the fish. On the other hand, in the water will provide cushioning against damage, to some degree at least, lacking in air. Six of one, half dozen of the other… Neale.>>

Re: Dragon Goby Stuck in Cave 5/6/12
I greatly appreciate you both for your help. Sadly it was too late for my favorite fish. Again thank you for your quick response.
Susan
<Thank you for this follow-up. Will share w/ Neale. BobF>

Brackish tank, stkg. 4/20/12
I have a 150G tank, and am wanting to convert it to a brackish tank from the fresh water that is currently is. My husband brought home a Colombian Shark without doing his research so I am looking to find out what I should/can keep in the tank with it to both make it happy and give the tank a "wow" factor.
<Well, for a start, two more Sharks! They are quite nervous, even shy fish that need the company of their own kind. When kept in a fair-sized group they will be much more outgoing and less likely to "pace" in one corner of the tank.>
Ideally I would like a fair amount of movement in the tank as well.
<For sure. The more water movement, the better. These catfish are migratory and do swim A LOT.>
I have been doing research on the brackish tanks and have got the setup and maintenance figured out I am just having issues finding solid information on compatible species and quantities as all the information I come across seems to contradict one another.
<Do you want to keep them (long term) with brackish livestock or marine livestock? Shark Catfish work very well with hardy marines like Lionfish, Snowflake Morays, Yellow Tangs, Arothron spp. puffers and some of the big but less aggressive Damselfish. So, if you're looking at that end of the salinity spectrum, you may want to focus on species able to live in marine conditions, such as Scats, Monos and "freshwater" Morays. Alternatively, if you plan on keeping them in a brackish system, then you might instead look at Sailfin Mollies, Fat Sleeper Gobies, Crazyfish, Knight Gobies, Shortnose Gar, Archerfish and Green Chromides to name a few. Any favourites among these? Scats consistently score well on the "fun" scale because they're friendly, beg for food, and become very easily tamed. The Silver Scat, Selenotoca fasciata, also happens to be hands-down one of the prettiest fish in the hobby, whether freshwater, brackish or marine!>
Thanks :)
Andrea
<Cheers, Neale.>

GSP with continuous gill problems 4/12/12
We would like to thank you in advance for any advice you can give.
<Most welcome.>
We have a 55 gal aquarium with 3 small Green spotted puffers, water temp is 80F, SG 1.008, nitrite and ammonia 0, nitrate .5, pH 7.4.
<All sounds fine, except the temperature is much too high. Aim for 25 C/77 F. The higher the temperature, the less oxygen water holds, and at the same time, the higher the temperature, the higher the metabolic rate of the fish, so it needs more oxygen than in cooler water.>
We have had these puffers for nearly 2 months the smallest puffer is slowly deteriorating , this fish relies on only 1 gill at a time for breathing he is slowly loosing interest in food and activity.
<This sounds serious. One possibility is a developmental abnormality: this fish was born with a deformed gill, and as it grows, this is causing steadily more and more problems. A second possibility is a gill parasite, but these are uncommon in brackish water fish. You could try placing the fish in full strength seawater for 20 minutes or so, and that should shift anything that infected the fish when it lived in freshwater conditions.
Repeat daily for a week. Thirdly, there's social problems, i.e., stress.
GSPs are not social animals and they do not coexist for long. While juveniles can be okay in groups, two males will squabble, as these are territorial fish in the wild, and the weaker male will be bullied by the stronger male. It's very common for the weaker male fish in situations like this to become shy, retiring, show less interest in food, and to grow much more slowly. As the size difference between it and the dominant male gets greater, then the problem of bullying gets worse.>
It has laboured breathing and retreats to a cave and flashes on decorations while the other fish show little or no symptoms. What should some one do in this situation?
<See above. If you can, separate the weaker fish to its own tank (even 15-20 gallons would be fine in the short term) maintained in a strongly saline environment, at least 50% normal seawater, SG 1.010, and maximise oxygenation. Feed a good variety of foods, taking care to minimise Thiaminase-rich foods (shrimp, mussels) while maximising Thiaminase-lacking foods (cockles, tilapia fillet) so that you can factor out dietary
problems.>
None of the fish show any signs of Ich or external problems. Thanks again
John
<Cheers, Neale.>
Re: GSP with continuous gill problems (RMF?) 4/12/12
Thanks Neil, I am considering what you wrote and I appreciate your time.
John
<Glad to help. Cheers, Neale.>
Re: GSP with continuous gill problems (RMF?) 4/12/12
Hello again Neale
<John,>
I have pondered your response at length, The green spotted puffer that is deteriorating routinely switches the gill that it relies on while clamping the other at times the fish will roam the tank with enthusiasm and I have witnessed it flinch as if it has been poked with a pin and then it will immediately retreat to its cave.
<Odd.>
These fish exhibit absolutely no animosity towards one another and can be often seen acting like a small team in their daily routines. We are watching the smallest GSP slowly die.
<Quite possibly, but is the fish feeding? If it is, that's good. I would separate them if at all possible. Have you tried the seawater dips yet?
These would eliminate some possibilities, making it easier to plan ahead.>
Any thoughts?
Thanks again
John
<Cheers, Neale.>

changing the tank up, BR stkg. rdg. 4/7/12
Im thinking of rescaping and possible reconsidering some of the stock choices in my 65 gallon archer fish tank...
What's it like now? Well firstly i have 5 healthy active Toxotes microlepis, and 4 (was planning on more, since i do know there schooling fish....the 4 were all they had and for 25% off too) boesemanni rainbow fish. Also an African knife fish who i will be re homing due to the slight aggression between the archers as they have their social hierarchy worked out (the king of the tank has changed to a completely black appearance while the others remain normal coloration).
<Ahh!>
-Basically the tank has root like driftwood on the far right side with thick plantings along the sides.... I'm thinking its a little too clogged up and thus some of the archers are sticking to staying under the "roots" due to the plants taking up some swimming space...
<What they do>
-So! I was thinking take out some of the Hygro and penny-Wort so all i have are the Val species, java moss, and java fern and sell back the boesemanni rainbow fish, and knife fish. Aso was planning on rescaping with maybe one or two pieces of the root like driftwood in the center of the tank and planting the java fern inside the lowly lit crevices. This leaving the back open area planted with the Val.s and partially on the sides too. All in all the main frontal space will be open and free with tall plantings along the sides and a dense "escape" of mangled driftwood in the center. Nice open, yet interesting layout.
-Why? Well i know the archers are "fine" in freshwater being the species they are but they are also found in low-end brackish (I'm curious as to the specific ranges they are found in in their natural habitat) Also this will be sort of a test to see whether they are more outgoing and active in freshwater versus low-end brackish, also health wise too.
-lastly, since only the archer will be in the tank... any opportunities for fish in the same requirement area of 1.003-1.005 sg to coexist with these mighty yet small species of archers?
<Quite a few... peruse here:
http://www.wetwebmedia.com/BrackishSubWebIndex/BrackishSubWebIndex.htm
Their not fully grown, the largest being 3" MAYBE 4" at the most. My lfs is awesome at getting in fish that id like mostly because i know the employees well (very lovely pop and ma run store) and I've given them excess plant growth and pointers/help with many of their oddball species. They also have an ACTUAL brackish tank, which is shocking since most stores don't bother with the correct conditions. So I've seen them have orange Chromides, and figure eight puffers, both of which seem to be fine at this sg?
<Yes>
Not saying id get either... just wondering what you would do?
<Read, consider my options/choices. Bob Fenner>
Re: changing the tank up, BR stkg. 4/9/12
I suppose the "freshwater moray eel" (not freshwater by a long shot I know)
is out of the question? As it requires a stronger salinity than 1.005?
<Likely so. B>

Gymnothorax tile help 4/5/12
Hello, I have bought a Gymnothorax tile about 2 weeks ago from a private listing. After getting to their house to pick up my new pet, I realized that he/she was living in horrible conditions. It was in a 10 gallon tank half full, with no salt, poor filtration, and horrible water conditions. After getting him/her home, I did a major tank clean (I know not the best idea, but his/her water was really that bad I had no other option), added water conditioner and let him be for a couple days. I then slowly started adding Instant Ocean marine salt, I do not know the exact measurements, I will be getting a hydrometer tomorrow,
<Yes, you'll need that.>
but I have added about 1 cup less than a half of a box (I was told that I should do half the recommended dose) that was specifically measured for a 10 gallon tank, which is what he is still currently in.
<Much too small. You should also get a larger tank in the near future.>
I have upgraded his filtration system to 2 filters made for 10-30 gallons, and added a heater. Right now his tank is about 28 degrees Celsius.
<24-26°C is enough. The water will carry more oxygen at lower temperatures, which should help a little in this small, uncycled system.>
He is currently on a steady diet of shrimp, they were feeding him cubed ham which after doing research I found was a big no-no, I will be introducing silversides into his diet tomorrow.
<Silversides can be fed regularly, but should not be the main part of the diet. It's important to get the diet mixed a lot. See http://www.wetwebmedia.com/ca/volume_4/V4I2/Freshwater_eels/freshwater_eels.htm >
Ok with all that being said, my Gymnothorax tile has been acting very strange lately. He seems to be struggling to breathe on and off throughout the day, flipping upside down and laying there for a few seconds, and then violently thrashing his tail back and forth creating craters in his sandy bottom. I am new to owning this species, and have done all the research that I can, but I just can't figure out if his behavior is normal.
<Likely an environmental problem due to the small and probably still uncycled system.>
Will he/she be ok, and is there something that I am doing wrong? Please help.
<The best for its survival would be to get it into a larger, well established marine system until you can provide a sufficient one. If you instead of that wish to use your current tank, get a test kit for ammonia and one for nitrates in addition to a hydrometer and more salt. The test kits will show when you should change water (basically you are cycling the tank with a fish in it now due to the major tank clean). Any ammonia measurement >0 or nitrates above 20-25 ppm are a reason for a water change. Also, keep the water surface moved with what filters you have available. When you reach marine salinity (check with the hydrometer) you can add well cured live rock to help with the filtration. In the mean time you should get a larger tank and start cycling it without fish. Later you can transfer your moray and the live rock to the larger tank and get rid of the small one or use it for something else.>
Thank you for your time, Stephanie
<Good luck. Marco.>
Re "Freshwater" Moray Eel Two Questions, fdg., sys. 4/9/12
Hi again, this is Alyson (the one with the "piggy" Gymnothorax tile) Since we last spoke I have been feeding him lesser and lesser each day to get him used to eating every other day. He is doing fine, keeps "begging" but I just don't look at him lol.
<Sounds good.>
I did have just two more additional questions....I was planning on purchasing another Gymnothorax tile and I have read on your site that they can live together and normally don't show any type of aggression towards one another.
<Yes, this works best if both (or more) are introduced to the tank
together, but adding another one generally works, too, with this species.>
I was just wondering if I do actually purchase an additional eel should I look for any "hints" that two are being aggressive towards one another <There may be an initial 'fight' at first contact, since one has established its territory, but if there are enough caves it should be no problem.
Rearranging some rocks/caves (without turning the tank into a cloudy mess of course) before adding the new one can also help.>
and also my specific gravity is already at 1.020-1.021....would this hurt the "new eel" moving him into that high of a level so soon after purchasing him?? (that's assuming the idiotic pet store has him in full freshwater, which they normally do)
<Acclimation can be rather quick. If you want to be on the safe side try this: Put the new eel with the water it was transported in into a bucket (add a small airstone if you have one at hand) with lid. Add tank water over about one or two hours until about 70-90% of the water in the bucket is tank water. You can use a cup or an air hose with a loose knot. Then, add the eel to the display or if available quarantine tank. The acclimation procedure can be combined with a small water change, since you have to replace the tank water you added to the bucket if you wish to avoid adding water from the store to your tank.>
I appreciate all of your help and hope to hear from you soon! Thanks
<Welcome. Marco.>
Re: Another issue Marco :(, G. tile 4/29/12
Hi again Marco, it's once again Alyson.
<Hello there.>
I feel so bad for pestering you with my questions/concerns :( I live in North Carolina, USA (do not know where you are located),
<Southern Germany, near Heidelberg.>
but I can not find vitamin supplements anywhere for my eel's food. There are 6 pet stores and no one has them and don't even know what I'm talking about (Haha I know right), so my question to you is there a brand/site that you can recommend so that I can order it over the internet for my eel?
<Vita-Chem Marine is not bad. A few drops on the food once or twice per week.>
Also, the only pet store in my city that has live rock is a very "dirty, sick animal type place" so if you can also recommend a good, trustworthy site to order live rock from? If so, that would be awesome.

I know in previous emails you have advised me to get a skimmer, trust me I am definitely saving up for one lol.
<Very good, this will help with waste removal and oxygen supply. Also keep the water surface moved to help with the gaseous exchange.>
I still only have the one Gymnothorax tile, but I ordered another one and it should be in Tuesday so wish me luck.
<Okay.>
Once again, thank you so much for all of your advice and help, although my eel is still laying his head sideways I am going to take your advice and not worry about.

Thank again and cheers to you too! :)
<Welcome. Marco.>
Hi Marco, another question 5/1/12
Hey again, hopefully this should be my last question for awhile ( I know you're probably thinking thank goodness lol). Since I cannot locally get the vitamin supplements for my eel's food, I was looking at your site and saw some things about being able to add baby and/or human vitamins to fish food.
<Yes, this can be done, although personally I rather use products developed for aquarium use.>
I spent all of today searching the site to see exactly (if so) what types of things to look for if I choose to go that route. I definitely need to add vitamins to Eely's food because although it's a variety, it is mostly frozen. If it is ok and safe to add baby and/or human vitamins, what should I look for and avoid when purchasing?
<Prefer sugar free liquid products high in thiamin.>
Also, how do I go about adding it to an individual feeding?
<Add a few drops after the thawing process and before feeding. If you feed larger foods (little fishes such as silver sides or clams, mussels, shrimps) you can also use a syringe to inject the vitamins into the food.>
And by the way, my new Gymnothorax tile should be in tomorrow (yay).
<Seems it's time to feed the old resident and rearrange some caves to avoid most territorial behaviour.>
Anything you know on supplementing human vitamins for "fish" vitamins would be awesome, if not I will have to order some online. Thanks again.
<Hope this helps. Marco.>
Re: Hi Marco, another question, BR 5/2/12
Hi again Marco, yeah I think I am just going to play it safe and order some vita-chem. marine over the internet. As far as preparing for the new eel
(still waiting for the pet store to call to say it came in) Yesterday I bought some more "caves" and what not and rearranged the tank decor so I am hoping that will help with the "new arrival" Thanks again for all of your help!
<You're welcome and I hope everything went well. Marco.>
New issue with eel laying with head sideways
Sigh....I thought for sure the last email I sent you would be the last lol.
<Oh... well.>
In previous emails I mentioned that my eel was laying his head sideways out of his cave. Well today he was very active, swimming around, exploring the new tank decor. That is when I noticed between his right eye and nostril, also his lower jaw, was very pale. The patches were not white nor did they look like a "fungus" of any kind. The patches are not on the other side of his face, but the reason that I am concerned is that when he did finally go back into his cave, he was rubbing against it on that same side.

I was searching your site and saw something about "white spot disease," but the pictures I saw didn't look like what is happening in my case. To be safe, should I treat for Ich??
<No. Not until you know it is Ich (Cryptocaryon irritans). You would notice heavy breathing and white, salt grain like spots. Healthy eels practically never get it due to their toxic slime coat.>
Other than his "scratching" he seems perfectly fine, happy with his new decor and such on, but once again any advice would be helpful. Thanks again!
<Check your water, ensure there is enough oxygen in the tank. Good luck.
Marco.>

BIG ammonia problem, need your expert advice again :( 4/15/12
Hello again it's Alyson and I have a BIG problem! I monitor the ammonia level in my tank daily and a week ago to my surprise, the level jumped to 2.5! I treated it with ammonia remover to see if that would lower it and it did to about .50 Well everyday after that it would go back to 2.0 would treat it and would go down. Well two days ago I tested it and the ammonia level was a whopping 4.0 so immediately I did a 50% water change and have been slowly raising the salinity level back to the previous 1.020-1.024 that it was. The fish seemed a lot happier (of course) and so I tested the ammonia level again last night and it is back at 2.0
<You started at 4.0, after a 50% water change you have 2.0, the math seems to be right. It also seems your tank is not cycled properly. In addition, you note you raised the salinity level after the water change. You should not change the salinity more than about 0.002-0.003 within a week to avoid a die-off of bacteria, which remove ammonia and nitrite. Those bacteria cultures need time to adapt to new salinities, therefore the changes should be limited to 0.002 per week, swings during a water change should be avoided. If you change water, be sure that the addition of new water does not change the salinity of the tank too much by addition of the proper amount of (marine) salt. Your morays won't be stressed by somewhat faster salinity changes, but ammonia removing bacteria can die.>
and now the ph level (which I've never had a problem with before) has gone down to about 6.5....What do I do?? Should I purchase a skimmer and have that along with my filter (which by the way is a whisper 200)?
<At marine or almost marine salinities a skimmer is always a good idea with regard to oxygen supply and waste removal.>
I am so lost. Along with the water change I also cleaned the gravel very well and was sure this would help my problem.
<Don't do this now. Gravel is also a habitat for bacteria. Cleaning it removes a lot of them, so you should only do that if your other filters can buffer this loss, which is no problem in a well established tank, a stage your tank apparently has not reached, yet.>
If you could please give me some advice or maybe if I'm missing something important I would be very appreciative and I know my fish would too.
<Carry on keeping ammonia down with water changes with proper salinity (use salt for marine aquariums and water with no ammonia) until your bacteria colonies have grown to a sufficient size, which will result in dropping ammonia. Feel free to add well cured live rock and/or a skimmer to accelerate the process by introduction of bacteria with the rock and/or removal of organic matter as one source of ammonia by the skimmer.>
Thanks again.
<Good luck. Marco.>
Re: BIG ammonia problem, need your expert advice again :( - 4/17/12
Thanks a lot Marco for your advice. I did not add any salt while continuing with my water cycling.
<You should add water of approx. the same salinity as the water you removed. Anything else will not be helpful for the cycling process. The salinity should be kept about constant throughout water changes.>
After doing countless water cycles, I got the ammonia level to 1.0 ( yeah I know, all of that hard work for a little change lol) I added some Ammo Lock and my ammonia is zero thank goodness! Now I am just slowly but surely adding salt back to the aquarium. Before all of the water cycling it was 1.024 now I am working with 1.010.
<This is a salinity swing, which could have been avoided by adding water with the same salinity as the water you removed. See the last email. You make it quite hard for ammonia removing bacteria to live and grow in your tank.>
So I have to raise the salinity slowly again (fun). In regards to adding live rock, the only pet store here that has it does not take good care of their animals at all and I am NOT going to buy anything from them. Also, In regards to the protein skimmer, would you guess that the two places that carry them are out of the size I need...So needless to say I'm going to
order a skimmer online and be happy with my current ammonia level! Thanks again!
<Cheers, Marco.>
Re: BIG ammonia problem, need your expert advice again :( - 4/17/12
Hi again Marco, I think when I originally wrote you what I was trying to say was that the water I was replacing was with marine salt, not that I was trying to raise the salinity level. I guess I misunderstood when you wrote back thinking I was not to add salt with the new water lol.
<Sorry, if I didn't write clear enough.>
I was confused because I was thinking why am I not to replace the salt water with salt water and after reading your latest email I think I didn't originally explain myself the right way. Needless to say, lesson learned and thanks again for walking me through it.
<Anytime.>
Have a good one!
<You, too. Marco.>
Too much stress for my Gymnothorax tile?? 4/27/12
Hi again Marco, Its Alyson again (the one with the piggy eel blah blah)
<Hi Alyson.>
I have some concerns/questions that I'm hoping you could provide me with your expert advice on. Well last week I upgraded to a 50in long 75 gallon tank so that I could transfer my fish into.
<Okay. Good size.>
It cycled for 5 days and yesterday I added the gsp, flounder and Gymnothorax tile to it. The puffer and the flounder were easy to move, the eel however was a different story. I removed all decorations (except for his cave) first and thought of an idea on how to move him. I had a half gallon milk container that I use a lot with water changes and put it in the tank thinking that when I removed his cave he would look for a hole to go into. Well....I took out his cave and he went nuts of course, he went into the container once, but before I could put the lid on and run him over to the new tank, he swam out. So, I put his cave back in and he immediately swam into it. I gave him about 10 minutes to calm down and tried to remove his cave again. He had wrapped himself inside the circumference of his cave (he was not coming out) so I got a bucket, filled it with his water, picked the cave up with him still inside and held it halfway in the water and ran him over to the new tank. (yeah it was a nightmare) I was very careful not to hurt him and does not seem to be injured in any shape or form. I know that it will take a few days or even weeks for him to "forgive" me. He is in his new tank (which has sand in now, no more gravel yay) staring out of his cave. Anyways, before this whole change he had already been on a hunger strike for 6 days and I know he will more than likely continue with it due to the stress of the move. So will he be ok continuing with this hunger strike?
<Should.>
I know they can go weeks without eating, but when should I start to concern about his eating?
<As long as the water parameters are in line and no signs of any disease occur (heavy breathing, changes of the skin or eyes, spasms...) you should not be concerned at all. Your eel was fed much too much in the beginning and likely has a lot of fat it can burn. Even one or two months is no problem as long as everything else is ok. Just offer something to eat every few days.>
Also, he is a lot darker now....I read somewhere that low salt can cause darker coloration, is this true?
<Not in my experience. The color can depend e.g. on illumination, at night many eels have a lighter color in general.>
Level is at 1.014 now. Any advice would be great. I really appreciate your site and all of your help that you have provided me with so far. My fish are lucky I found you because if not they could have been dead by now lol.
Thanks again!
<Sounds like you are doing fine. Check your water parameters regularly, since the tank is quite fresh and slowly rise the salinity. with time. Good luck. Marco.>

"Freshwater" Moray Eel Two Questions 4/1/12
I want to start off by first thanking you guys for your wonderful site!
<Thanks for your kind words.>
I have been maintaining my brackish water tank using all of your incredible advice. Well on to the questions....First off I have a 40 gallon brackish water tank PH is at 8, nitrates and ammonia levels are all normal and temp is kept at 80 deg F. Started off by having gravity level at 1.010, but have slowly over time raised it to it's current reading of 1.021. In the tank I have a "freshwater moray eel" or as you refer it to a Gymnothorax tile, a green spotted puffer and a "freshwater" flounder/flatfish.
<Not the best tank mates, these eels can become really incompatible when growing up.>
I first purchased my eel about two months ago and of course he went on a hunger strike, but after raising the salt levels to 1.021 the eel has been eating. My concern is he is eating like crazy! He accepts food by tweezers and his diet is consisting of freeze dried krill, shrimp, muscles, silverbacks, ghost shrimp and tilapia (I like to keep his diet varied). I read on your site that juveniles tend to eat every other day and adults eat twice a week. My eel eats two times a day each time taking two different foods. He doesn't seem to just be stuffing himself because when he has "had enough I guess" he goes back into his cave. Is this normal for him to eat like this??
<Oh, that's what I often ask myself about some people.>
I feed him at a specific time in the morning and at night and he is readily waiting for me, sometimes barely letting me get the food in the tank. When I first got him (assuming its a he) he was very skinny about the circumference of a dime and 11in long. Now he is almost the circumference of a nickel and 13 in long. My question is, should I keep his feeding habits the same, or if not what amount he should eat?
<You offer much more to him than nature does in my opinion. I'd feed significantly less, about the size of the eel's head per feeding. Feeding every other day is sufficient. There are some reports on the negative results of overfeeding moray eels, e.g. by P. Purser in the TFH book and there are examinations of eels caught in nature showing they don't eat every day (some larger species only once per week or less.>
My next question is, I read that when juveniles, the eels live in brackish water and eventually move to full saltwater when older.
If this is true, when should I convert to a full saltwater tank?
<It's easier to maintain, because you can use a skimmer, live rock. You've almost reached marine salinity, so I see no reason to not convert to full saltwater.>
Thank you so much for your time and I look forward to hearing from you!
<Also see: http://www.wetwebmedia.com/ca/volume_4/V4I2/Freshwater_eels/freshwater_eels.
htm . Cheers, Marco.>
Re: "Freshwater" Moray Eel Two Questions 4/1/12
Thank you very much for responding so quickly!
<No problem.>
I am going to reduce my eel's food starting today. Do eels beg?
<If by begging you mean that they expect to get food from a known source: yes. In some areas moray eels accumulate below the nets of large offshore fish farms. Every time the fish within the nets are fed, the moray eels come out to get their share, which falls through the net.>
Lol, because that is going to be the hardest part in reducing his diet. He literally "begs" by sticking half of his body out from his cave and faces towards the surface waiting for me to feed his fat butt when I come in the room every morning. In regards to his tank mates the green spotted puffer and the flatfish, so far the eel is very accepting of them, but I will watch as he gets older to see if he acts aggressively towards them. Thanks again for all of your help!
<Welcome. Marco.>

Stressed Figure 8 Puffer; beh., sys. 3/21/12
I have recently purchased two Fig. 8 Puffers. I have them in a 20 Gallon tank (Soon to be 29) with 3 Dalmatian Mollies.
<These are fun Pufferfish, but can be very nippy, so watch your Mollies carefully. Expect to rehome them, and be pleasantly surprised if you don't.>
The smaller of the two (approx 1 inch) Has 0 problems. Eats, sleeps, navigates etc. The larger Puffer (approx 1.5-1.7 inches) he's been stressed the whole three days I have had him.
<Environment?>
I read that having two puffers should be O.K. in a 20 Gallon but I cannot find anything on whether the Mollies could be adding the stress factor.
<Can do. Although nippy, this Pufferfish species isn't especially aggressive, and very small specimens are easily spooked (they often go dark in colour when stressed). Male Mollies can be aggressive and may harass smaller fish. Watch them carefully, and see how the two species are interacting. In and of themselves the Mollies shouldn't scare the Puffers, but it _could_ happen.>
My Ammonia and Nitrites are at 0. Nitrates at 5-10 mg/l And PH at about 7, maybe 7.2?
<Way too low. These are BRACKISH water pufferfish, so you should be adding not less than 5 grammes marine aquarium salt mix per litre of water (about SG 1.003 at 25 C/77 F).>
Was a little lighter than 7.4 rating on High Range PH Test Kit. I have a tall drift wood piece in the back right corner with a cave like rock set up against/next to it. In the front left I have 6 6in. grass weed and spiral grass as well as 2 10in spiral grass. I have one more rock with a hole in it looking as if it were some sort of entryway into the "Plant Field" if you will. I can send you a picture if you like. I am just wondering if it is too cramped for the larger puffer ATM. Will the 29G help? Do I need more plants for hiding? Should I get an even bigger tank? Will removing the Mollies help until I get the larger tank? Any information would be so greatly appreciated. Thanks you very much, Steve.
<My assumption here is that the environment is wrong -- switch to brackish, and see what happens.>
P.S. Don't be afraid to get very scientific/elaborate with descriptions. I live with a Marine Biologist and a former Aqua Culture Major.
<Real good. Cheers, Neale.>
Re: Stressed Figure 8 Puffer
So I have been reading years worth of your answers the past few days for Fig.8 Puffers. You repetitively say "Use Marine Aquarium Salt" Is that different than just a regular Aquarium Salt?
<Yes. Absolutely.>
What I have consists of 1 ingredient, NaCl.
<Correct. Sodium chloride, also known as table salt. This is not the same thing as the salts (plural) that make seawater or brackish water. While adding aquarium salt works in the short term, it lacks the full range of salts including those that raise hardness and pH, e.g., calcium carbonate, sodium bicarbonate, magnesium sulphate. So by all means use up your box of aquarium salt. But once it's done, switch to a marine aquarium salt -- the generic brands at your local big-box pet shop will be fine. Use just the same way, but in the knowledge that long term, your fish will be healthier.>
Expect to rehome Mollies? Pleasantly Surprised if not? Elaborate if you don't mind?
<You may get lucky. I'd guess that 1 in 4 of these Figure-8 Puffers turns out to be completely peaceful and ignores, for the most part, its tankmates. But the odds aren't in your favour, and some can be persistent fin-nippers, and a very few are outright psychotic.>
From my observations, The Mollies aren't bugging the puffers at all when it comes to nipping.
<Good.>
the male Molly is constantly harassing my females but I don't see any nips on tails or anything as of now.
<Sounds about typical.>
It is a brackish water tank. SG is at 1.004 ATM.
<Cool.>
So I am not sure if that changes any opinions. ALSO. Was the PH too low or the NO3?
<The pH. Ideally, and certainly if you'd used marine aquarium salt, the pH would be around 7.5, an ideal level for low-end brackish water fish such as Figure-8 Puffs.>
You really seem to know your puffers so I am very grateful for you to be the respondent. I can send a picture if it will help.
<Thanks for the kind words. Cheers, Neale.>
Re: Stressed Figure 8 Puffer
I also forgot to mention that I have about 75 snails. Not sure what specie they are but since I have added the puffers, most of them have retracted into their shell and move very little since the introduction of the puffers.
<Well, yes! Snails aren't as stupid as they look. Often they become nocturnal in the presence of predators that nip them. Do also be aware that most snails will die in brackish water (though the Malayan Turret Snails, Melanoides spp., thrive in brackish water).>
Also, since adding the deadwood this morning, The puffer seems to be less stressed over the past few hours.
<Ah, now, is this bogwood from the pet shop or random wood from the garden?
Both will lower the pH, and that WILL upset low-end brackish water fish.
Again, higher carbonate hardness (measured with the KH, not GH, test kit) will prevent this, so that's another reason to favour marine aquarium salt.
Plain sodium chloride doesn't affect the pH at all. On top of this, regular wood from the garden can carry across toxins like pesticides, and to my cost, I've seen what this can do, and very quickly.>
So maybe I just need to go get a larger tank. ALSO I have a very large filter for my tank. So large that the lowest setting still causes somewhat strong current. Possible adding factors?
<Brackish water fish generally enjoy strong water currents, being adapted to tidal habitats and all! Cheers, Neale.>
Re: Stressed Figure 8 Puffer
Pet shop Wood. It was my friends from a former tank of his. cleaned thoroughly with a tooth brush and very hot water. I also soaked it prior to that in practically boiling hot water.
<Should be fine then. But do check pH. If it sinks below 7, you have a problem.>
My girlfriend works at a local pet shop so I am going to have her pick up the Marine Aquarium Salt and a few more plants tonight.
<Hmm… would skip the plants unless you're sure they're salt tolerant. Up to about SG 1.003 most hard water-tolerant plants (like Vallisneria, Amazon Swords, etc.) are fine; but above that, few do really well, and most just die.>
So should I just keep an eye out for snails that haven't moved for several days and pitch them or should I thoroughly inspect them and assure they are living?
<Yes.>
What is the meaning of this statement "(measured with the KH, not GH, test kit)"? was it just a point of favoring marine aquarium salt or something I need to use for my tank?
<Two kinds of test kits, carbonate hardness and general hardness. General hardness is measured in degrees dH or mg/l calcium oxide and is often called the "GH" test kit, e.g., by API. Carbonate hardness is measured in degrees KH or mg/l calcium carbonate and is often called the "KH" test kit. Both tell you something about the aquarium, but carbonate hardness is the best measurement of how well water buffers against pH changes. General hardness mineral salts have little impact on pH changes, so in this context, such a test kit is far less informative. Cheers, Neale.>
Re: Stressed Figure 8 Puffer 3/21/12
Well I don't have any real plants. I was just thinking of adding 2-4 more taller types of fake grass and a few pieces of slate for proper caves and thick area for Mollies to hide and breed.
<Sounds good. Do see some of my recent messages on decorating brackish water set-ups.
http://www.wetwebmedia.com/brackishsubwebindex/brackishdailyfaqs.htm
With care, you can create a unique style that doesn't look like a failed marine or freshwater system!>
As well as the snails. How large are the few snails mentioned that thrive in brackish water?
<Well, Nerite snails are often brackish-tolerant, but mostly small, at most an inch in shell width, though quite globular, so pretty chunky-looking.
Clithon spp. for example are widely traded and do well in brackish water.
Some of the Neritina species will do well too. Otherwise Melanoides spp.
are good choices, but they breed very quickly, and can become pests.>
If so could I probably acquire them from a local shop? Any suggestions on brackish water set ups? I potentially want to get a 40G+ and try to breed Puffers. Any pointers?
<Breeding puffers is very difficult, and only one or two species do so even halfway readily under aquarium conditions. The best species for this are either Carinotetraodon lorteti or Tetraodon suvattii, both freshwater.
Cheers, Neale.>

New Dragon Goby Worries, inverts, and questions about testing 3/22/12
Hi there,
I have a brackish tank. The salinity is 10.10.
<Do you mean a specific gravity of 1.010? At 25 C/77 F, presumably --
temperature matters here.>
It is housing four mollies, a dragon goby ,
<Will eventually need a 55 gallon system.>
two bumblebee gobies and two fiddler crabs. It is a 29 gallon tank. The substrate is sand. The issue is with the filter, or rather, filters. We have gone through three in the past two months. We have tried tetra brand, whisper, and Marineland. The Marineland is the current filter, and it is making a horrible grinding noise, the same as the others before they quit working.
<Well, there are two things to consider. The first is you get what you pay for, and there are good reasons expert fishkeepers buy expensive filters like Eheim units -- they last a lot longer. They might cost twice as much as a cheap Chinese filter, but these German filters will last 5 or 10 times longer. But I don't think that's the issue here, though it may be a factor.
I suspect your Goby is digging (as it should) and throwing sand into the filter. Check if there's sand in the media inside the filter. Sand will grind away inside the filter, and cheap filters especially quickly die under that sort of stress. In any case, move the filter somewhere that keeps the inlet well away from the sand. One approach is to put flat rocks underneath the filter, and confine the sand to the rest of the aquarium. Do also check the filter isn't sucking in air bubbles. A carelessly positioned air stone can cause all sorts of problems!>
I can't afford to keep buying entire filter systems twice a month. Any ideas what may cause this? How can I keep it from happening again?
Thanks,
Becky
<Cheers, Neale.>

Salt-Marsh Environment 3/19/12
Dear WWM,
<Bryce,>
I recently found some Fiddler Crabs at the local pet store. They were, of course, being kept in a freshwater tank with no way to get air. I did not purchase any, but I did start doing research. I will be working at a science center this summer, and I think that a Salt-Marsh Ecosystem display would be really neat.
<Can be, and you do see such terrariums at many public aquaria, zoological collections.>
It would consist of approx. 70 gal. long tank with a fine sand substrate. Do you think that four inches of sand would be good or more?
<Hmm… unless you're growing plants, would minimise the substrate. While the crabs can dig burrows, they dig into mud, and plain sand doesn't "shore up" adequately for that. So, if you wanted burrows for the crabs, better to use plastic or ceramic equivalents (such as PVC tubes covered with sand) and minimise the actual depth of sand to whatever is needed to hold the rocks in place and to provide a realistic terrain.>
If so how many?
<Would keep a fair-sized group to minimise aggression, and ideally more females than males. Anything upwards of 6 should work, but in a tank this size, and that would leave space for Mudskippers. But if just the crabs, then easily a dozen or more.>
Should the water be kept at more 1.000 or 1.015?
<Anything between 1.005 and 1.010 should be adequate.>
Is there a way to purchase the grasses and other plants that grow naturally in the marsh not online?
<Yes, they can grow, but with some complications. Firstly, you'd need a substrate with mud of some type at the bottom (a few inches of pond soil would be fine) topped with an inch of sand for aesthetics. Secondly, grasses tend to need strong lighting, I'd have thought at least 3 tubes the full length of the tank, and probably 4 or more. Daylight, if possible, would be even better.>
What are some of the most common species of plant that would grow in the region?
<Many, many types. Aquarists generally have the impression there are few brackish water plants, but that simply isn't true. Unfortunately, few are traded, so you do need to do independent research here. The Aqualog brackish water fishes book has a fair summary of salt marsh plants, but you'd be better off reading something like Dynamic Aquaria if you can for a full listing of species and their salinity preferences.>
What types of rock would be best? Limestone, Granite, Sandstone, Lava Rock? Drift Wood is okay or not?
<Any and all, though the system might look better with a single type of rock as that's what you'd see in the wild. Bogwood is also useful. A few nondescript shells like oysters and mussels can add variety, perhaps heaped into a "drift" like you'd see in the wild, or with the oyster shells cemented to rocks to form a reef.>
The tank would have a small section of brackish water on either side. What foods would be best to feed them?
<They're very omnivorous, so virtually anything edible. Algae wafers, frozen krill for calcium, bloodworms, soft fruit...>
Would heat lamps be good for keeping the entire thing (open air) warm or should a heater be used?
<Any, so long as the air doesn't get colder than, say, 20 C/68 F. I'd probably go for the heat lamp if the water was shallow; also consider the under tank heat mat.>
Would an aerator be enough for the small ponds of brackish water?
<If necessary, yes.>
Thanks for all your help.
Enjoy life this week!
<Will try!>
Bryce
<Cheers, Neale.>

Re: Mudskippers! – 3/7/12
Hey thanks Neale! (by the way the group of Toxotes microlepis is doing great!
<Real good.>
Their eating the cichlid pellets and Hikari carnivore pellets and they also love the freeze dried shrimps but of all else, live crickets go the fastest. So just wanted to thank you again for your suggested ideas for pellet food! I even have a video of them if your interested or if you need me to get a few pics of them up close for ID or reference needs)
<Sure.>
so from what its looking like in my 20 gallon i could house a very minimal amount of the dwarf Indian mudskippers or other wise known as Periophthalmus novemradiatus.
<Yes. The Indian Dwarf. Nice fish. Small enough that aggression isn't usually lethal.>
Im panning on a diy background that will have a terraced descending pools of water with sand so its not all just one flat incline from water to land....and also i will then be able to use the height of the tank as well.. and even make a waterfall with an internal filter! Oh the possibilities!
<Indeed. While an authentic mangrove look would be nice, the fish couldn't care less. So long as they have stuff to climb on, they're happy.>
So how many would you suggest for a 20 gallon system with maximum surface area in mind and of course tons of hidey holes and perching spots? 2? MAYBE a trio?
<Would get more than that; 5 or more. Overstocking is the key here: in smaller groups, you will likely end up with one bully and the others being picked off over the months.>
I'm reading their naturally aggressive as its in their nature.
<Yes. Males, at least.>
lastly just out of curiosity.... has there been success with keeping them alongside red claw crabs or any of the semi terrestrial brackish water crabs?
<Not Red-Claw Crabs, no. They're dangerous to small 'Skippers, and meals for the bigger species. With Mudskippers this small, best to keep on their own or with harmless algae-eaters such as brackish water Nerite species.>
Probably wouldn't work at all but just wondering...
thanks again!
-John
<Cheers, Neale.>

Mudskippers! Stkg./Sel. 3/6/12
Hey there everyone! Well as always, I've been scheming up new tank ideas here and there...and recently have found myself attracted to mud skippers!
So while i have just started researching i had a few questions that primarily will determine whether i will/should keep these cool creatures.
So here are a few questions....
1. Yes or no- Are there any species that would work out for a 10 gallon tank?
<Not really, no. Many would be fine with just 10 gallons of water, but you'd need dry land on top of that, so realistically, you'd want 20 or 30 gallons for even the mini species like Periophthalmus novemradiatus, the Dwarf Indian Mudskipper.>
2. If no to the first question: Are there any species of mud skippers that would be fine in a small group in a 20gallon tall tank which has been tricked out to maximize the use of the 'tall' portion via roots/ DIY background with a waterfall to take up more space in the 20 gallon?
<See above.>
3. probably what i should have asked before.....whats the smallest commonly imported mud skipper species?
<Again, see above.>
4. is low end brackish, being around 1.025 in salinity a good water salinity for these guys?
<Half-strength seawater is ideal, so SG 1.010 at 25 C, but anything from 1.005 to 1.025 at 25 C is generally fine.>
was just wondering those few things before i dove into the specific of care requirements...
thanks!
-John
<Cheers, Neale.>

F8 Puffer/BB Gobies possible Eggs? 2/21/12
Good Evening.
<Hello,>
I have 2 Figure 8 Puffers and 3 Bumblebee Gobies in a 35 gallon planted tank (Java Fern, Java Moss) that has been established for approximately 4 months. I was taking a glance at the back of my tank this evening and found 12 yellow vesicles placed in the sand of the back corner. They are a yolk-like color and approximately 2-3mm in diameter. I have done some research on Bumblebee Goby reproduction, and the egg sac description is nothing like what I have found in my tank.
<Indeed?>
In addition, there isn't any behavior that would make me think that it was a spawning-related issue -- at least in regards to the Bumblebee Goby (egg placement on wall/ceiling of cave/hideaway, protective nature over eggs, etc).
<Yes; usually the eggs are laid on the roof of a cave; see the cover of my Brackish Water Fishes book for an example.>
Could it be possible that these are Figure 8 eggs?...granted, nobody really knows the reproductive habits of the Figure 8 puffer.
<Quite so.>
There are no large snails in the tank, just feeders (I have seen many feeder snail egg sacs…nothing like this...) I've been looking online and cannot find anything that matches this scenario. Any information would be greatly appreciated.
<Well, there seems to be few reports of spawning behaviour, though some aquarists (e.g., Frank Schaefer) have reported seeing eggs in their T. biocellatus aquaria. Some Tetraodon species extend brood care, e.g., T. fluviatilis, with the male guarding the eggs until they hatch. But others have been reported to be simple egg scatterers, as with T. schoutedeni. In all cases the fry small, so a major problem is rearing the fry, with foods like infusoria or Cyclops required initially rather than brine shrimp Artemia.>
My most recent chemistry as of 1730 on 2/20/12:
pH: 7.4
Nitrite: 0
Ammonia: 0
Nitrate 10
SG: 1.003
<All sounds good for this/these species.>
Thank you for your help!
Billy
PS. Sorry to email twice so soon, but I'm noticing some things about my one Figure 8 Puffer that is really making me think that it's her eggs that were the objects I mentioned earlier. I know it seems very VERY hopeful, but '2' is swimming vigorously, and searching around the patch of sand where the aforementioned vesicles were lying.
<Could be foraging for food…>
I say 'were' because I saw a BBG begin to eat them, so I took a 60cc syringe and was able to save 5 of them. They are currently in the syringe on a small patch of gravel that was sucked up under them when I drew them up, and the syringe is sitting in my tank...it was sterile out of the packaging.
<Hmm… would put these in a breeding trap near a good water current. Well worth seeing what hatches!>
Anyways, '2' also keeps chasing away anything that comes close to that patch of sand…including shrimp (but doesn't try to eat them at all, just nips once and turns away). I know that puffers hunt pretty much 24/7, but this wasn't the hunting behavior I see for feedings/snail hunting. So, now I'm kind of wondering what I should do with the...well, hoping, eggs. Keep them in the syringe and in the tank? Make a 1 gal with cycled water from the original tank?
<Would keep the eggs in the aquarium you have for now, perhaps using a breeding trap, and do read up on rearing Tetraodon fry generally. Many reports on T. suvattii for example, and a few on T. fluviatilis.>
Any ideas would be great. Thanks.
<Very exciting! Good luck, Neale.>

Puffer Eyelashes? 2/15/12
Hello!
I've looked everywhere and I have yet to find anything that answers my question.
Ever since I purchased my first green spotted puffer, I've been fascinated by these fish! I like learning new things and I've been stumped when trying to figure out what this was. I was hoping you could help me in identifying what exactly the two "eyelash" looking things on my figure 8 Puffer's face are and what they could be used for. They are positioned just between his eyes and protrude by roughly one millimeter.
Thanks,
Chris C.
<Those are its nostrils. They're actually very interesting. Most fish have nostrils not connected to the throat (so they can't breathe through them -- the fact our nostrils are connected to the throat is something we inherited from our Lungfish ancestors). Fish use their nostrils exclusively for smelling. Now, Puffers have a skull almost completely filled with proportionally massive muscles to operate their small but exceedingly strong jaws. That means there's little room inside their head for anything else. Evolution compensated for this by giving Puffers eyes that bulge outwards compared to other fish, and putting their nostrils on the outside of the head. Those little tentacles are the tissues used to detect smells in the water. Hope this clears things up! Cheers, Neale.>

finding and selecting low range hydrometers, BR and SW f' 2/5/12
Hi WWM Crew,
Your site is pretty much my aquarium bible. Its great! And i have recommended it to a number of workers in my LFS as well as friends. Especially after I overheard some really awful advice being given to a customer at which point I kind of inserted myself into the conversation and offered some advice. Probably should have minded my own business but the clerk obviously had never heard of the nitrogen cycle or prime (which was right there on the shelf) and was selling a bunch of fish to a guy to put in a tank far too small for the number and size of fish he was purchasing. I had to speak up, as politely as I could, but i did manage to educate both of them a bit. I'm no expert, and a year and a half ago i was clueless, but I have studied and read and read and read and now i feel like I'm probably approaching the intermediate level of freshwater fish keeping. I now also have a low to medium salinity brackish tank with only Black Mollies (2 females and 1 baby which has turned out to be a Dalmatian and is now big enough, about 1/4 to a 1/2 inch long, so it wont (shouldn't) be eaten. All 3 are doing very well in this 10 gallon tank. The tank was bought to be a quarantine tank, but I couldn't leave it empty, so after a month of fishless cycling and finally getting the Am and nitrites down to 0 and also, just to be sure, i added a little pure ammonia and watched to see how it was handled, , it disappeared pretty quickly, nitrites briefly bumped up a little and in a day or 2 i was back to Am=0, Nitrites=0 and some nitrates. I then moved 2 mollies from my freshwater tank to this 10 gallon and over time have worked up the salt . I currently use 3 level tablespoons (the measuring spoons, not the food spoons) of Instant Ocean per 10 liters of water with a tiny bit of prime (1/8 cap or so) per 10liters of water change. The tank came with a whisper 10 HOB filter which in my opinion is not adequate for a 10 gallon tank, but rather than replace it with a Whisper 20 I bought a 2nd Whisper 10 to run in parallel, now i can alternate filter swaps and not upset the nitrogen cycle too much. Also, and this is cool, i found 2 cheap sponge filters that fit nicely on the whisper intakes and provide a little more area for nitrifying bacteria to grow in along with keeping any big particles out of the filter. They work great. I just buy empty filter cartridges, I don't use carbon unless I see a particular reason to use it for a week or so. The tank has plenty of plastic plants and a cave, so its not too plain. I also have a large round (4" diameter) air stone which the mollies love to play in, its funny, they actually will swim over the stone and allow it to float them up, then swim out and do it again, after awhile they get bored and go off to do something else. Temperature is 80F, Am is 0, Nitrites are 0 and well, you know how nitrates are, they always climb, but i try to keep them below 20mg/l. I want to measure the SG using a glass hydrometer , the trouble is that the scale i am interested in is 1.000 through say 1.010 or possibly 1.015and that tends to be very low on the hydrometer scale. I just donï¿½ï¿½t trust any instrument thatï¿½ï¿½s reading close to one end or the other of its full scale. With that in mind I went looking for a suitable hydrometer. They are quite hard to find but I did find these three: http://morebeer.com/view_product/18650/102224/Hydrometer_-_Final_Gravity http://www.austinhomebrew.com/product_info.php?products_id=2089
http://www.stevenson-reeves.co.uk/hydrometers/LANS.htm
They are used primarily in beer and wine brewing . I was leaning towards the first link, the 3rd link seems to have a lot of choices but its nearly impossible to understand what the ranges are, at least for me its extremely confusing. All of those in the 3 links above would need to have their readings temperature corrected. Can you comment on what would be a good choice for my application? Are they even appropriate if i adjust the reading for temperature? If not, what do I do, i suppose i could mix, measure and call it "close enough" but I'd rather know what I really have in there. One more thought, I really noticed a striking change in the mollies when they got into the salted water, they seem much healthier. When they were in the freshwater tank, I had one that had some white stuff on her belly and an especially large glob near the anal fin, I couldn't diagnose it, I watched it for over 2 months, it wasn't Ich, the other molly is coal black and if it was Ich this would have spread. My guess was Columnaris, so i treated the tank for it. It didn't help a bit. But after I moved her to the new tank and brought up the salt (marine salt) level I noticed a distinct change and a definite improvement, so whatever it is, its getting better around the anal fin and as to her belly? Well, maybe she's half Dalmatian. I really donï¿½ï¿½t know but her baby is definitely a Dalmatian. I'd send a picture but there must be some magic to getting a good shot, I just can't get a decent photo. I need to say one more thing for those reading your site, use a maintenance log program, and log every single thing that you do, measurements, fish deaths, stuff added from chemicals, to salt to plants, lights changed, water changes and how much (I use a bucket with 5 and 10 liter marks on the outside as it seems like almost everything in the fish industry that matters is metric), log it all, it's worth its weight in gold when you can look back and see what is really going on i your tank, not just what you think you remember. I have a log for my 10 gallon and a separate log for my 44 gallon tank. I use Aqua Log, its free and if you set up the columns before adding any data it will be nice and orderly and its simple to use.
Thanks
Eric
<Hello Eric. The short answer is that any hydrometer that runs from 1.000 to 1.030 is going to be useful for fishkeeping. However, a couple of issues. First, it needs to be calibrated (i.e., accurate) at a useful temperature, e.g., 20 or 25 degrees C. If the calibrated temperature is far above or below these, it's less useful. Second, any hydrometer (or refractometer) is only as accurate as its design allows, and consumer grade ones costing a few pounds or dollars will be less reliably accurate that scientific ones costing tens if not hundreds of times more. The best way to be sure is to make up a known concentration (e.g., 35.5 grammes marine aquarium salt in 1 litre of pure/RO water) at the calibrated temperature (e.g., 25 C) and then test the hydrometer. If thoroughly dissolved, which may take 20 minutes or longer, 35.5 g/l should be 1.025 at 25 C. If your hydrometer is far above or below that, then make a note of how far, and adjust accordingly when using the hydrometer. To be honest, brackish water fish largely don't care, so if you're dosing at 5 grammes/litre, an ideal amount for Mollies, you should register SG 1.002-1.003 on your hydrometer, but if its a bit above or below, no worries! Go with salinity (grams/litre) over hydrometer reading any day of the week. Fish experience the salinity; specific gravity is immaterial. Cheers, Neale.>

Gymnothorax tile eating shrimp 2/5/12
Hi there.
<Hi Niki.>
My eel eats 2 frozen shrimps every week. Today I was feeding him a shrimp on a kebab stick when he ripped the whole shrimp of the stick and swallowed it whole! Usually he would only bite off a bit and eat the rest later. After swallowing the shrimp I could clearly see the shrimp inside of him (A big bump formed inside him - about in the middle of his body). He swam around the tank a few times and then retreated to his cave. I went back a few minutes later still seeing the shrimp inside him. Is this okay?
<Yes, no problem, when it can be swallowed, it's apparently not too large.
Try to keep the diet more varied:
http://www.wetwebmedia.com/fwsubwebindex/fwmorayart.htm>
Thank you Niki
<Welcome. Marco.>

Gobioides compatibility 2/4/12
Hello WWM Crew,
<Hello,>
Have done a little research but am really just looking for a definitive answer and understand you are the people to go to.
<Nice to know!>
Want to ask the question before I get the tank as opposed to making a mess of it after it's stocked and too late.
<Sure.>
I'm looking to start a brackish tank, low end brackish. I'd love to stock a Violet Goby and Bumble Gobies (Brachygobius nunus, the more brackish type I believe). This leads to my first question, I know a Violet Goby prefers a SG of 1.010 as optimal and the Bumblebee Gobies are happiest at 1.005 to freshwater.
<Both will be perfectly happy at SG 1.010, or indeed anything between about SG 1.005 and 1.010. Contrary to popular misconception, Bumblebee Gobies (BBGs) aren't specifically freshwater fish or brackish water fish. The imported species at least (and identifying it is virtually impossible)
appears do well in both. Above all else diet is the reason BBGs die. They can actually be pretty adaptable in terms of water chemistry.>
Will the Violet Goby be happy to drop down to 1.005 SG with no adverse health effects or is it going to be best if these two don't go in together?
<They're an odd mix, and your problem isn't salinity but feeding. The BBGs will be a total pain in the backside when it comes to feeding because they're so slowly and picky. You'd be hard pressed getting them to eat enough with the Violet Goby slurping everything it sees! I'd go with a more active, midwater goby to be honest. Perhaps something like Knight Gobies or Clay Gobies (Dormitator lebretonis) or even Crazy Fish (Butis butis), all of which are fairly available in the hobby. With a bit more effort, you could alternatively track down species such as Eleotris fusca or a brackish-water blenny like Omobranchus zebra.>
Second question is, where does this leave me in terms of further stocking?
So far been looking at Guppies and Mollies. I know these can be easily acclimated to brackish but am concerned that they will eat all the food before the two Gobies get a look in.
<Certainly strong competitors with regard to the BBGs. Violet Gobies aren't so difficult to feed because they're big and easily tamed. Throw in some live brine shrimp and watch them scarf them down! They also eat bloodworms and algae wafers, which the livebearers won't eat too quickly.>
So is there any other sort of oddball fish that will co-exist happily with these two.
<Other gobies would be ideal; see above. Do read:
http://www.wetwebmedia.com/BrackishSubWebIndex/VioletGobyCompF.htm
Small livebearers can be excellent. Rather than Mollies, why not Endler's or else something out of the ordinary -- Micropoecilia picta or Micropoecilia parae. Both of these are colourful and fun to watch, and while not easy to obtain, they are both traded as well as available through livebearer associations.>
Something outside the norm a bit. Seeming as live food will be going in frequently, feeding won't be a concern and picky eaters are welcome. I've been looking at the Freshwater soles, but would be concerned on the larger species predatory nature and also the aquarium floor would be getting kind of crowded by that point wouldn't it?
<Freshwater soles are very difficult to feed, and I'd recommend keeping them alone or else with small, day-active tankmates only (the afore mentioned livebearers would be ideal). Soles feed at night mostly be smell, so you can ply them with wet-frozen bloodworms and brine shrimp easily enough, but if there's anything competing at nighttime, they'll starve.
Best keep on their own, in groups if you want, in a smallish tank specially set up for them.>
Would love to hear your opinions!
Thanks for reading,
Sam
<Cheers, Neale.>
Re: Gobioides compatibility 2/4/12
Thanks for the speedy response Neale, much appreciated.
<Most welcome, Sam.>
Will have a look the species you mentioned, then speak to my local fish store and see what is likely to be available. As you may have noticed I'm a fan of the Gobies so glad to see a few more options!
<Real good.>
Just found your book on Amazon and have ordered a copy, try and rack up a little additional information before 'taking the plunge'.
<Ah, now, there are two outstanding Goby chapters in this book -- neither written by me! One by Naomi Delventhal, a scientist who studies gobies, covers lots of different goby types and lists their specific needs. The second is by Richard Mleczko and covers mudskippers. You may be surprised to learn there are a few mudskippers that never leave the water (such as Apocryptes spp.) and these are discussed. They aren't commonly traded, but you can get them once in a blue moon, but in the US you'll find Frank's Aquarium a good channel for getting these sorts of fish:
http://www.franksaquarium.com/brackish.htm
While I've not bought anything from Frank (being on the wrong side of the Atlantic) we've crossed e-mails now and again and he seems a good egg. He seems to have Apocryptes bato in stock, and in the freshwater section (for some reason!) he has a few euryhaline species that can be kept in brackish and/or marine aquaria, such as Hypseleotris leuciscus and Giuris margaritacea. He sometimes has Hypseleotris compressa in stock too, a stunning freshwater to marine species that exhibits lovely colours when breeding. These "Gudgeons" are fairly widely sold in the UK, but apparently less so in the US, perhaps because they come from Australia and New Guinea and the export chain isn't so well developed to the US. Whatever the case, they're nice fish well worth keeping. Most are carnivorous, hardy, and territorial rather than aggressive.>
Thanks again for letting me pick your brain.
Sam
<Cheers, Neale.>
Re: Gobioides compatibility 2/6/12
Have just received the book and had a quick thumb through. To be frank I'm absolutely amazed at the number of fish that can live in brackish conditions. The common opinions seems to be that you're limited to a tiny number of species, this is clearly not the case.
<Quite so.>
Very taken with the number of Gobies on offer. Going to try to recreate a mangrove looking tank using various driftwoods to represent roots, a few large rocks and a soft sand substrate.
<Sounds fun.>
Stocking a Butis butis, Stigmatogobius sadanundio and of course the Gobioides broussonetti! Figuring that as long as I can carve the tank up into a few clear territories, add some disguised PVC pipes to the sand and add lots of cover, they should co-exist peacefully.

Got my eye on a nice sized tank that I think will accommodate all fish happily.
Would love to try my hand at mudskippers, but feel that due to the territorial nature of the other fish in the tank it might not work well.
<In any event, Mudskippers don't really mix well with "proper" fish anyway.>
May be a better life if a dedicated species tank was set up for them.
<Assuredly so.>
Something for the future certainly. Unless one of the Apocryptes spp. would be happy in with the other fish?
<Does depend on the tankmates. They don't handle aggression or nervous tankmates well, but smallish, harmless tankmates such as small livebearers and smaller gobies could work.>
I'm under the impression that they spook quite easy and aren't happy around the more boisterous tank mates.
<Indeed. In the wild they live in inch-deep water, where they feed on algae and whatnot. Needless to say, with so little swimming room and things like wading birds hunting for them, they have to react to sudden shadows and noises very quickly.>
I think I may be on your side of the Atlantic! Live in the UK. I know the email address is a bit of a false lead. Had it since before AOL made its push over seas and started offering ".co.uk".

How successful is ordering fish online usually?
<Generally very good. Aquarium shops like Wildwoods have built up a good sideline doing this sort of thing, with few reports of problems.>
Prefer to be able to see the fish myself before purchase and have always been apprehensive about placing an order. Is this unfounded or can there be complications?
<If you think about it, the fish in an aquarium shop were air-freighted there. So there's little risk to shipping fish if it's done right.>
Thanks again! Your information and opinions have been absolutely invaluable.
<Glad to help.>
Cautiously optimistic about my upcoming project!
<Real good.>
Sam
<Cheers, Neale.>

New Dragon Goby Worries, inverts, and questions about testing 2/1/12
Hi There!
<Salve!>
I just purchased a 6-in or so Dragon goby and two Bumblebee gobies to join my four mollies and two fiddler crabs in my brackish tank. It's a 29 gallon. The sg is at 1.010 and the Ph is 8.2. I have it set at 81 degrees.
<Bit warm. 25 C/77 F is ample.>
When I got my gobies home, I checked the salinity of the water from the store. Even though they had a special "brackish" section for these fish, the sg was still only 1.002.
<Fine for short-term care. At least there was some salt in the water, and that'll make all the difference.>
I slowly added water from my tank to acclimate them over about an hour.
They seemed fine with it. However, when I added the dragon to the tank, I noticed a small, pimple-like round white dot on his fin, near the gills.
Also, it seemed that the sand in my tank looked like it was "sticking" to the fish. I hadn't noticed this either at the store or in the bucket. I'm not sure this is normal. He is, however, digging and burrowing. I have seen him feeding by sifting through the sand, so he is eating. We fed brine shrimp and algae pellets yesterday.
<OK.>
I'm not sure how to treat these symptoms given the presence of inverts in the tank. I'm fairly certain that most medication I've looked at has said it is not suitable for the inverts. Any suggestions?
<Well, for now, I'd not worry too much. Brackish water kills off most freshwater parasites quite quickly, and at SG 1.010 you shouldn't have problems with Whitespot or Velvet. Indeed, fungal infections are very much suppressed too. So for now, just observe. Physical damage should heal itself, and unless you see a secondary infection set in, you won't need to treat at all.>
Also, in regards to testing on a brackish tank: should I use a kit designed for salt water?
<A good question. Ideally, the latter. But ammonia and nitrite kits should work equally well in both, as should pH test kits, though some freshwater pH test kits won't be accurate or easy to read above 8.0.>
We had been using the test strips. Yesterday I also brought home a Salt Water test kit for Ph, Ammonia, Nitrite, and Nitrate. Boy, what a difference in readings! The strips had been leading me to believe all was well. However, the liquid kit is showing a high ammonia and Nitrites at 2 ppm.
<Could simply be variation in quality. Dip strips aren't notably accurate, and good quality liquid tests should be more reliable. Test kits have a shelf life, too.>
I added a microbe-lift Nite-Out product for Ammonia and Nitrites, however if it not down by the time I get home today I'm going to do a water change as well. Am I right in thinking the new liquid test is more likely to be correct?
<Likely so.>
Thanks!
Rebecca
<If the Goby is happy and eating, don't be too concerned. They're very tough in brackish water, being adapted to living inside burrows under mudflats. They should coast through any slight bumps while they settle into their new home. Cheers, Neale.>

Help! dieing violet goby dragons! 2/1/12
I have raised a violet goby dragon for 3 years living in 39 gallon tank,
<Water quality?>
and was about to upgrade to a much lager <drinking or larger?> tank. It is 16 inches long and doing great until recently. He has developed a mouth desies that causes his lips to bleed and peel. But that isn't the worst part. He is doing fine.
<?!>
It is the new babies i bought. they get the sickness and it is far more deadly! I have lost 3 and a 4th is soon to go. For the babies it shrinks there head in around the eyes, mouth and fins peel, red gills, and finally surface swimming until they die. They die within a few days of attracting the sickness. I have been performing water changes like crazy, and adding Melafix and recently also Pimafix.
<Both worthless>
I thought it was fin rot because of the other fish and they are healing nicely, but not the baby dragons. I have 3 babies left and like i said 1 is about to die, another has just contracted the sickness, and the last one doesn't seem to have it yet. Please help me as i do not want the others to die. These are amazing fish and i love my adult dragon, it almost seems like he listens and understands me. It would kill me if i lose him to.
<... what? Are these animals in a brackish setting? Read here:
http://www.wetwebmedia.com/BrackishSubWebIndex/VioletGobyDisF.htm
and all the linked files above. Bob Fenner>
Re: Help! dyeing violet goby dragons! 2/1/12
> <... what? Are these animals in a brackish setting? Read here:
> http://www.wetwebmedia.com/BrackishSubWebIndex/VioletGobyDisF.htm
> and all the linked files above. Bob Fenner>
Ok thanks. Ya i have been checking water quantity lots and it is fine,
<... subjective evaluations are of no use. Figures please>
but i have been using aquarium salt
<Not useful either. Need to use marine salt... synthetic sea salt. READ where you've been referred to. B>
and not nearly enough. I will switch immediately to marine salt. But it isn't just the dragons affected. I lost a loach, unknown why, the girlfriend threw it out while i was away. there is a blue grammy that is going red, and a pelco bottom feeder that has what looks like a big cut in his head and it is growing a white mold on it. The fish are all starting to make a come back by the way, i hope that is a good sign for the dragons. The dragons mouths still have mold looking stuff on them. What medican would you recommend instead of Melafix or Primafix? And i realize that some of my wish wont last in that high of salt water, i will have to move them to another tank.

Help black tipped shark catfish dying 1/26/12
Hello
I have a 60 gallon bow front and 2-7" shark cats. I have had these 2 for a little over a year. Today when I arrived home from work they were both nearing death with scratches on them and what looks like a slime covering their body. All of their fins were shredded, swollen anuses, a film over their eyes, and these guys have been in great health up until today. About 3 weeks ago I lost my first fish in years in this tank. He was a 7" electric blue acai cichlid. I am concerned about what is causing this. I did a 50% water change, added some salt, and dosed the tank with Melafix. Symptoms are unnoticed until they are floating and I watch my fish nightly.
Thanks in advance for any help.
Dash
<Hello Dash. Need some information on this aquarium, in particular, water chemistry and salinity. Shark Catfish are brackish to marine animals, so you need quite strongly brackish water for them to do well. Given you have a freshwater cichlid with them, my assumption is that you've tried to keep them in freshwater -- something you shouldn't do. Furthermore, adding "some salt" doesn't really tell me very much about the salinity. The specific gravity should be SG 1.003-5 for juveniles up to about 10 cm/4 inches in length, and above that, you really do need around half-strength seawater (SG 1.010) to fully marine conditions. Get and use a hydrometer, and then test the salinity. Do read:
http://www.wetwebmedia.com/ca/volume_7/volume_7_1/ariidae.html
Do also review your choice of medication; Melafix isn't much rated as a cure, despite it's cheap price and attractive marketing. At best, it's a preventative, something to use if a fish is damaged by transit or fighting
but not yet infected or sick. My guess would be these fish are sick because of a poor environment, and until you fix their world, they aren't going to get any better. Cheers, Neale.>

Red Claw Crabs 1/25/12
Most people on the internet seem to think these crabs are mostly aquatic, I saw that you guys say they are mostly land.
<They will'¦>
The problem I have is that my crabs never come out of the water (I've only had them for four days, so I shouldn't say never).
<Quite so.>
I do have the tank set up as aquatic only with a few bits sticking out of the water. But still, they seem to only like the water. So, I guess my main question would be, why do you claim they are mostly land crabs
<Because they are -- in the wild at least. They live in mangrove forests feeding on leaf litter and carrion. Do read up on Perisesarma species, which is what these are.
http://en.wikipedia.org/wiki/Perisesarma
They're shore crabs, If they don't come on land in your aquarium, then something is amiss. They won't come out if there's something scaring them, or if the air is too cold or too dry. They're also EXTREMELY territorial, and if one crab claims the one small bit of land, the others may not be "allowed" out.>
and is there a resource that can give me a step-by-step on how to set up and care for these crabs?
<Not that difficult. Set up something like you'd create for mudskippers, with a couple inches of warm, brackish water (SG 1.005 at 25 C/77 F is fine). An under tank heater would be ideal. The rest of the tank can be sand, rocks, bogwood. Make sure the air inside the aquarium is warm and damp, but a slight flow of air is important to prevent mould. Keep the hood secure because these animals WILL escape if they can. Use filter floss or plastic mesh to plug any large gaps. Crabs are cannibalistic at times, especially when moulting, so provide lots of caves and such hiding places.>
I am also wondering how you know so much about them, and speak with such authority when there seems to be so much miss-information out there?
<Because I'm clever. More seriously, because I'm a marine biologist by training, an aquarist by inclination, and I've spent some 20-odd years reading scientific as well as hobby literature on brackish water animals. Perisesarma spp are classic brackish water, mangrove crabs. There's really nothing at all mysterious about them. Yet unscrupulous retailers continue to sell them as "freshwater crabs" or "aquatic crabs", and willfully ignorant aquarists vigorously resist any attempt by people like me to tell them what these animals need to do well. It's significant that the people who succeed with them, e.g., actually breed them, are those who understand their ecology and provide brackish water for the adults and marine conditions for the larvae. Cheers, Neale.>