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Blue Spot Jawfish Feeding?


Boboli

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I bought a blue spot jawfish two days ago. He has made himself very comfortable in his new home digging many holes under one group of rocks! He can be seen most of the day peeking from one of his holes.

My issue is I have been trying to feed him with a feeding stick and tube using many different foods, krill, mysis, flake and pellets. He is very agressive he acts like he wants to eat it but only puts it in his mouth and spits it back out.

Does anyone have experience with these cool fish?

Any help appreciated!

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Best thing I can suggest is getting rid of it before your $100 go belly up. Blue Spots are a very new fish to the aquarium trade, they were only discovered in the early 90's.

 

They do require a very large aquarium of atleast 75g. They are very territorial and prefer to be one of the only fish in the tank. Unlike many other jawfish who eat most offerings, bluedots have a very specific diet.

 

They prefer a very open sandbed with light structure which is why a larger tank and very few other fish are required. The fact that it is such a new species, a very pretty fish, there is not a whole ton out there on them as far as write ups. Best advice, unload it fast !

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I had a BSJF for over a year and she was super healthy, ate like a pig and was my favorite fish by far. Originally housed in a 14g BC, then moved to a 50g. It may take a couple days to get used to your tank, and start taking food. I fed mysis,squid, and brine to mine and she seemed to love it. I would just keep offering food and in the next day or two it will eat.

Few things to take note:

#1 thing is to have a COVERED tank

#2 COVERED TANK

#3 COVERED TANK

When spooked and it happens a lot, they will jump! Jump through a pin hole, like ninjas. A couple people on NR are keeping them, with lots of success. Deep sand beds, make sure your structure is on the bottom of your tank, and keep it covered. They are super fun to watch swim, have tons of character. Enjoy

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I had a BSJF for over a year and she was super healthy, ate like a pig and was my favorite fish by far. Originally housed in a 14g BC, then moved to a 50g. It may take a couple days to get used to your tank, and start taking food. I fed mysis,squid, and brine to mine and she seemed to love it. I would just keep offering food and in the next day or two it will eat.

Few things to take note:

#1 thing is to have a COVERED tank

#2 COVERED TANK

#3 COVERED TANK

When spooked and it happens a lot, they will jump! Jump through a pin hole, like ninjas. A couple people on NR are keeping them, with lots of success. Deep sand beds, make sure your structure is on the bottom of your tank, and keep it covered. They are super fun to watch swim, have tons of character. Enjoy

Cool thanks for the advise ! , and I specifacly covered the tank for this fish!

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Best thing I can suggest is getting rid of it before your $100 go belly up. Blue Spots are a very new fish to the aquarium trade, they were only discovered in the early 90's.

 

They do require a very large aquarium of atleast 75g. They are very territorial and prefer to be one of the only fish in the tank. Unlike many other jawfish who eat most offerings, bluedots have a very specific diet.

 

They prefer a very open sandbed with light structure which is why a larger tank and very few other fish are required. The fact that it is such a new species, a very pretty fish, there is not a whole ton out there on them as far as write ups. Best advice, unload it fast !

I'd say you're pretty misinformed here. These fish were described in the 90's but have been collected by Richard Rosenblatt since the 60's.

 

It's not true that they require "at least" 75g: plenty have them in nano tanks with success. They do not "mind" other fish (very similar to other jawfish in terms of territoriality) - I believe many get the impression they are much more aggressive than yellowheads because they are extremely territorial with *conspecifics* of the same sex. With other fish they will generally just flare, push them, or spit sand at them - never bite or injure. I would agree, however, that the more surface area and open space the better: however, as you can see by this video, they are found with (some) live rock. A minimalist tank is probably best. Tankmates should be chosen carefully: slow moving fish and preferably no bottom-dwellers would be ideal.

 

I don't know where you got the idea that they are much more picky than other jawfish: I have had them accepting pellets within their second day and they seem to eat especially well once established (mind you, most of my yellowheads have had to be trained to eat pellets). Many consider these to be delicate fish - it is believed that this could be due to bacterial infections from unsanitary handling and because of a drastic change in temperature from where they are collected. The Sea of Cortez can reach the 80's in temperature, but, during some months, the temperature generally hovers around the 60-70 degree mark.

 

1 year is not long term, read some fish mags latley there are a lot of stories on them the show they do not do well long term in a nano....

1 year would be a decent time to see if a fish will work out "long-term" in my opinion. There are plenty of marine biologists (namely Scott Michael) and sources that would likely disagree with the assertion that they require large tanks. Some do agree with you as far as tank size (Bob Fenner comes to mind), but I see them as pretty similar to yellowheads. Just my opinion.

 

Cool thanks for the advise ! , and I specifacly covered the tank for this fish!

I would try a pipette as opposed to a feeding stick. Try turning off the pumps while feeding and perhaps soak the food in garlic - mine love mysis and pellet. They are wonderful little fish - good luck! :happy:

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Per Bob Fenner Not-So-Nano is correct. They are a colder water species, they require a great deal of space, and they are not keen on tank mates. Having had one for more than a year I was lucky (per Fenner whom I believe unquestioningly) to get her on pellets and to last as long as she did. Also per Fenner she was clearly a "she" based on her markings.

 

Link:

http://www.wetwebmedia.com/BlueSptJawArt.htm

 

Addendum to OP: If you are dead set on keeping him then you may want to skip the feeding stick, let him settle down for a few days, and then start feeding pellets. You may get lucky and he will survive in your tank. Also the advice about covering the tank... Mandatory. They are notorious jumpers. And it is how I lost mine at the end. I accidentally left the screen off one day and she got spooked by something and I found her later as fish jerky.

 

If you check my 60 gallon tank thread you can see photos of her living in my overflow (it was a good food source and a quiet place away from other fish).

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Per Bob Fenner Not-So-Nano is correct. They are a colder water species, they require a great deal of space, and they are not keen on tank mates. Having had one for more than a year I was lucky (per Fenner whom I believe unquestioningly) to get her on pellets and to last as long as she did. Also per Fenner she was clearly a "she" based on her markings.

 

Link:

http://www.wetwebmedia.com/BlueSptJawArt.htm

 

Addendum to OP: If you are dead set on keeping him then you may want to skip the feeding stick, let him settle down for a few days, and then start feeding pellets. You may get lucky and he will survive in your tank. Also the advice about covering the tank... Mandatory. They are notorious jumpers. And it is how I lost mine at the end. I accidentally left the screen off one day and she got spooked by something and I found her later as fish jerky.

 

If you check my 60 gallon tank thread you can see photos of her living in my overflow (it was a good food source and a quiet place away from other fish).

 

Thank you much for bringing that article to light, that is the exact reference I had read from along with others in hobbiest magazines that basically say the same thing.

 

"Foods/Feeding:

 

There are Jawfish species that have a broader diet, consuming worms, crustaceans et al. infaunal material; the Blue-Spot is almost exclusively a zooplanktivore"

 

This is the other thing that I was going to bring to mind but I could not remember what exactly they did eat that was differnt from other jawfish. Even if they do take pellets I would think the pellets vs zooplankton would be differnt nutritional value ?

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Thank you much for bringing that article to light, that is the exact reference I had read from along with others in hobbiest magazines that basically say the same thing.

 

"Foods/Feeding:

 

There are Jawfish species that have a broader diet, consuming worms, crustaceans et al. infaunal material; the Blue-Spot is almost exclusively a zooplanktivore"

 

This is the other thing that I was going to bring to mind but I could not remember what exactly they did eat that was differnt from other jawfish. Even if they do take pellets I would think the pellets vs zooplankton would be differnt nutritional value ?

Nutritionally, pellets are not the best choice in the first place (for any marine fish): however, as far as accepting them, I have had no problem with them eating them. They're convenient and are fine now and then in my opinion. The yellowhead jawfish are zooplanktivores as per stomach content analysis as well so there shouldn't be any difference.

 

Per Bob Fenner Not-So-Nano is correct. They are a colder water species, they require a great deal of space, and they are not keen on tank mates. Having had one for more than a year I was lucky (per Fenner whom I believe unquestioningly) to get her on pellets and to last as long as she did. Also per Fenner she was clearly a "she" based on her markings.

 

Link:

http://www.wetwebmedia.com/BlueSptJawArt.htm

 

Addendum to OP: If you are dead set on keeping him then you may want to skip the feeding stick, let him settle down for a few days, and then start feeding pellets. You may get lucky and he will survive in your tank. Also the advice about covering the tank... Mandatory. They are notorious jumpers. And it is how I lost mine at the end. I accidentally left the screen off one day and she got spooked by something and I found her later as fish jerky.

 

If you check my 60 gallon tank thread you can see photos of her living in my overflow (it was a good food source and a quiet place away from other fish).

I believe I did mention Bob Fenner in my post, but there aren't very many others who agree as far as care for this species. In my opinion he is overestimating their delicacy (although jawfish in general require special care for sure): I've come in contact with many of these jawfish personally and they are usually not much more difficult to care for than yellowheads (except they seem more prone to bacterial infections in the beginning).

 

As far as temperature, again, there is a wide fluctuation:

Diving Sea of Cortez

I have found a chart that measured the average temperature of each month but haven't been able to dig it up. There are many fish found in this area (namely Longnose Hawkfish) which have no notes of cooler temperature requirements - in my opinion, (again JMO), temperature is not as important because they are exposed to so much variation, but it may be important to start by mimicking the temperature they are naturally found at when first introduced. It may be argued that they are fairly deepwater fish, but juveniles can be found quite close to the shoreline (per Scott Michael) where there is brighter lighting and a warmer temperature. Not to mention they have spawned in temperatures up to 82 degrees.

 

I don't know why you would believe Fenner unquestionably when other marine biologists disagree. Additionally, he is incorrect in stating that they can be sexed simply by the color and size of spots. There has been a lot of research done on sexing them (you can read an in-depth attempt here by breeder Matt Pedersen) and there has been no reliable way to sex them other than the size of the head and possibly the vent. Just my opinion, but, as long as they are provided with the proper care, they are a fine community fish (when kept with *carefully* chosen tankmates). Sorry for the wall of text - I just (personally) think there is a lot of misinformation about this species. ;)

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Thanks for the info all who replied!

I did get him to eat one chunk of krill this evening, but on my second attempt he denied it by spitting it across the tank.

Well progress anyways.

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My comment about Fenner is because he has, historically, been correct in his findings/recommendations, has years of experience in the hobby/trade, and cites sources and data considered to be based on empirical research by noted authorities in the given field not anecdotal "see I did it! So you can too!" type posts by hobbyists.

 

I will be happy to change my opinion, JaneG, if you would be so kind as to cite your sources of "other biologists" and the papers they have written on the subject of BSJ. To date in my own research I have found quite a bit of information on the various web sites dedicated to the hobby but collectively the posters have been hobbyists not Marine Biologists who have done research on the subject of the BSJ, tend to fall into either the "I did X and the fish was Y so it should work because I did it once" or they reference Fenner.

 

Speaking of which the closest "scholarly work" I could find outside the original work done by Allen & and Robertson was the article in Reef Keeping which used Fenner's work as its foundation.

 

As to sexing... Did you bother to actually read the reference you posted? If you did you would find that the male clearly displays a "white" coloration during mating and the female remains brownish...

 

As to pellets... Extrapolating the research done on the subject for commercial fish farms [1] we find that the following is required:

protein 18-50%

lipid 10-25%

carbohydrate 15-20%

ash < 8.5%

phosphorus < 1.5%,

water < 10%

trace amounts of vitamins, and minerals.

 

Looking at Sallifert Pellets for example we find:

Protein 65%

Lipids 15.5%

Inorganics 12%

Glucans / Polysaccharides 7.5%

Moisture max 7.5%

Omega-3 HUFA 30mg/g

DHA / EPA >2

Vit. A 30000 IU/kg

Vit. C 2000 mg/kg

Vit. D3 2500 IU/kg

Vit. E 400mg/kg

Antioxidants: Ethoxyquine BHA/BHT.

 

Which puts us right in the window for what would be considered a "healthy" fish diet.

 

So, JaneG, please post your references and works disputing the facts listed in Fenner et al.

 

[1]http://pubs.ext.vt.edu/420/420-256/420-256.html

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Thanks for the info all who replied!

I did get him to eat one chunk of krill this evening, but on my second attempt he denied it by spitting it across the tank.

Well progress anyways.

Great! These fish can take a little while to settle in but it sounds like he'll do fine.

 

My comment about Fenner is because he has, historically, been correct in his findings/recommendations, has years of experience in the hobby/trade, and cites sources and data considered to be based on empirical research by noted authorities in the given field not anecdotal "see I did it! So you can too!" type posts by hobbyists.

Bob Fenner has been incorrect before. For example, he stated that Harlequin Shrimp will *only* eat live starfish - yet mine have been fed exclusively frozen coastal starfish (and, believe it or not, hake - frozen FISH) for more than 6 months. This does not revole around "see I did it! So you can too!" ideaology - you could argue Bob Fenner is doing the same by saying they cannot be kept in nano tanks ("I had bad success in a nano tank with this species - it must need a larger tank" thinking). As for other marine biologists and well-recognized "hobbyists":

 

Kevin Kohen, director of LiveAquaria says "these fish can adapt well to most reef aquaria that are maintained between 70-80 degrees"

 

Scott W. Michael talks about this species in "Basslets, dottybacks & hawkfishes:plus seven more aquarium fish families" as well as "Reef Aquarium Fishes"

 

As per fishbase: "Tropical" as opposed to "subtropical"

 

Again, the temperature varies

 

These are about as authoritative as can be. Again, the fact that pairs have spawned in warmer tanks (I can find more mention of this if you would like) should be proof enough that they can be comfortable in warm temperature tanks and the fact that species found in the Sea of Cortez (Angelfish, Hawkfish, Damsels, Wrasse, Tangs, Moorish Idols, Blennies, Cardinals...the list goes on) have no "notes" for temperature requirements. This could be due to a (possible) illusory correlation between bacterial infections or disease and water temperature. Does this species probably do better in a tank around the early 70's? Possibly - but they can obviously do fine in warmer tanks. Does this species probably do better in a large tank? Possibly - but what fish doesn't if given access to food and the like?

 

I will be happy to change my opinion, JaneG, if you would be so kind as to cite your sources of "other biologists" and the papers they have written on the subject of BSJ. To date in my own research I have found quite a bit of information on the various web sites dedicated to the hobby but collectively the posters have been hobbyists not Marine Biologists who have done research on the subject of the BSJ, tend to fall into either the "I did X and the fish was Y so it should work because I did it once" or they reference Fenner.

 

Speaking of which the closest "scholarly work" I could find outside the original work done by Allen & and Robertson was the article in Reef Keeping which used Fenner's work as its foundation.

First and foremost: Bob Fenner is - to my knowledge - not a marine biologist and should not be accredited as such: per his website, he has "a couple of life science degrees and a teaching credential for chemistry, physics and biology." Next, Henry C. Schultz III's well-known article on jawfish for ReefKeeping magazine uses *multiple* sources yet makes no mention of said requirements. In fact, the article goes against Bob Fenner's recommendation of a minimum substrate length of 3'', instead suggesting a much larger minimum. Quite simply, you will be hard-pressed to find a lot of information about this fish outside of captive requirements because - they're jawfish. There's not much more to say about them besides that. This is the same reason hours of research on lots of fish turn up little to no scholarly work (which, by the way, Bob Fenner writing an article for a magazine does not necessarily equal "scholarly work"). Some information can be found on diving sites, however.

 

As to sexing... Did you bother to actually read the reference you posted? If you did you would find that the male clearly displays a "white" coloration during mating and the female remains brownish...

Did you read what you posted? You said that you must have clearly had a female - "per Fenner she was clearly a "she" based on her markings." If I am to believe the implication that you think your jawfish was female simply based on lack of color change, then you're wrong: males will not flash without the presence of a female. What Fenner said was:

"females with dark-brown bodies and larger blue spots"

He goes on to say that males will change color before spawning. The above statement implies the opposite (females certainly don't change the size of their spots before spawning) - which is very likely incorrect.

 

 

As to pellets... Extrapolating the research done on the subject for commercial fish farms [1] we find that the following is required:

protein 18-50%

lipid 10-25%

carbohydrate 15-20%

ash < 8.5%

phosphorus < 1.5%,

water < 10%

trace amounts of vitamins, and minerals.

 

Looking at Sallifert Pellets for example we find:

Protein 65%

Lipids 15.5%

Inorganics 12%

Glucans / Polysaccharides 7.5%

Moisture max 7.5%

Omega-3 HUFA 30mg/g

DHA / EPA >2

Vit. A 30000 IU/kg

Vit. C 2000 mg/kg

Vit. D3 2500 IU/kg

Vit. E 400mg/kg

Antioxidants: Ethoxyquine BHA/BHT.

 

Which puts us right in the window for what would be considered a "healthy" fish diet.

 

So, JaneG, please post your references and works disputing the facts listed in Fenner et al.

 

[1]http://pubs.ext.vt.edu/420/420-256/420-256.html

Ah, but this takes all the ingredients - even nonusable - into consideration. I would suggest reading this:

Different forms of marine fish food

I can elaborate a bit myself, but it pretty much hits it on the nail:

 

The binder used for these forms of fish food is wheat, gluten, or other land products. These products cannot be digested by marine fishes. ...since wheat contains protein, the total protein of the product is given on the package, but not all that protein can be used by the fish, so the protein content on the package is misleading as to what is the ‘usable’ protein.

 

Protein is essentially one of the best indicators of a "healthy" food. Additionally, many of the "vitamins" and "supplements" in pellet foods "wear off" when open and at room temperature.

 

I hope you don't mind the thread takeover TS!

 

Jane

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