Blue Spot Jawfish - 3rd time the charm?

That's how my pair Opistognathus randalli behaved. Most of the time you would just see their noses sticking out. Those guys where huge (in length and diameter) and capable of swallowing feeder shrimps the size of a fully grown skunk cleaner shrimp. I suppose they could eat small fish as well, which is one reason why I'm a bit hesitant to add a pair of these guys to my 100 gallon tank.
I had them with another pair of smaller jawfish (no sure which species, likely O. variabilis), a pair of marine bettas and a pair of anemonefish, either clarkii or sebae.
To feed them well I had to drop them frozen shrimps right into their moth via an acrylic tube.

I wonder how they would behave on their own...

BTW: with Opistognathus randalli (Gold-specs jawfish, aka Tiger jawfish) males and females can easily be distinguished: the females have a black spot in the front portion of their dorsal fin, males don't have this spot:

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Top: male, bottom: female

I wish the Blue Spots were that easy to sex.
 

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After swapping burrows several times back and forth (with some force involved) it seems tha larger one has settled for now to build its home under the left rock and leave the right for the smaller one.
By now they are busy stealing pebbles from each other with the larger one clearly winning. Though the smaller one is constantly trying to steal some back - it's just hilarious.

They are eating like crazy and look like pregnant potbelly pigs.

It's also interesting how they dispose of their waste: they make their little rat-poo pellets inside their burrow and then take it into their mouth and blow it out into the water where the flow carries it away. The other one then sees it floating by and has to check if it is something edible, only to blow it further away when he discovers that it's a poo pellet. It's just funny to watch.
 
Still doing good. Seems they have settled in by now.
They also get along fairly well. There are some little squabbles, nothing physical, but rather contests who can make itself look largest.
It's either a pair or two females. Since they have slightly different head shapes I still hope for a pair. But from the pictures of males I found I would now say the smaller one's head shape fits that of the known males better than that of the larger one.

The larger one is for sure the more busy builder and much better in the "procurement" of pebbles.

They eat a lot - I guess I need to check if there is any ammonia buildup or if the old DT water and the live sand get the job done.

Here another video of them:

<iframe width="560" height="315" src="https://www.youtube.com/embed/CLq_g2Nt95Y" frameborder="0" allowfullscreen></iframe>

BTW: in the background, in the next QT, is my new pair of bluestripe pipefish. (right side)
 
They look great. I'm assuming the tank they are currently in is a QT, correct? If so, what size DT are they going in, and will it be a dedicated species tank for them?
 
I have no idea yet where to put them in the end.

Originally I wanted them for the 100 gallon tank, but that may not be ideal for them. If I put some jawfish in there it will rather be some west pacific species like O. randalli or O. variabilis.

I have a 20L that I used as a treatment tank for some of my regal angels. The last of them will leave it this weekend. I may use that tank for now for the blue spot jawfish as a species tank. Size wise it should be enough for a good while.

These guys are really funny - I've never seen a potty trained fish, but these guys are. They take their poo out and also leave their burrow to pee. They really like to keep their burrow clean :D
 
Sounds like someone needs a new aquarium?

Always :D

Though my wife may not agree to another permanent tank. She is already nagging about the 5 QTs I have lined up in the living room for about a year now.

If I set up a tank for them I may at some point add a pair of latezonatus since they also like it cooler. Though such a tank may still be too warm for Catalina gobies (they may also end up getting eaten :()

BTW, if these guys like cooler waters, what about Clarion and Passer angels?
 
Very nice! Hopefully there will be some development soon... Unlike o.aurifrons who sometimes share burrows in captivity even if they aren't a pair, I think rosenblatts don't share holes even as a pair unless they're spawning...so it seems it's a good sign they're living in close quarters without any hiccups[emoji1360]
 
Yesterday I measured Ammonia with an API kit and it was at about 2 ppm. Though the Jawfish didn't show the slightest signs of discomfort.
I added some Amquel to get the Ammonia down for now and plan to do a larger water change later today.

I also added more live sand and gravel so they can do more constriction and to add more bacteria substrate.

I would need some micro and macro organisms that live in the sandbed - maybe I got to make a trip to the beach and see what I can sift out of the sand there.
So far I added a good load of tigger pods, but they will not last very long - the Jawfish even pick them off the sand.

I also need to find some larger compatible sand zone inverts for their later tank: sea stars, snails, hermits, shrimp, ... Anybody knows a supplier of California native species?
 
They are still doing good and stuffing themselves with as much food as I throw in.
The thing that confuses me a bit is that the skimmer is not removing anything and not producing any dry foam. I cleaned it to make sure there isn't an oil film on it, but no change. Only after I added some Clarifi-SW it started removing something.
Can Live Sand cause such a strange skimmer behavior?

Anyway, here the latest video of the two after I added more sand and gravel to their QT:

<iframe width="560" height="315" src="https://www.youtube.com/embed/SDDw4OdTwBM" frameborder="0" allowfullscreen></iframe>

The smaller one seems to be more aggressive which leads me to believe he may be the male.

This was a pair DD sold some time ago:

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There is clearly a difference.
Right now my guess would be that the bottom one is the male.
 

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I'm still trying to figure out the ideal temperatures for these guys, so I did some searches. This is what I found:

"... In the tropics, the thermocline can be quite shallow on average, as in the eastern Pacific (50m), or deeper as in the western part (160-200m). ..."
Source: https://www.esr.org/outreach/glossary/thermocline.html

"... Cabo Pulmo to San Lucas and even farther north operators are getting to the seamounts. In winter and spring water temperatures can drop to the low 60s. Visibility is lower (25-40 feet), but generally improves to 80 to 100 feet by late summer, when the water warms to the 80s in the Sea of Cortez. ..."
Source: http://www.undercurrent.org/UCnow/dests/MexicoPacificInfo.shtml

"Sea surface temperature (SST) is the water temperature close to the ocean's surface. The exact meaning of surface varies according to the measurement method used, but it is between 1 millimetre (0.04 in) and 20 metres (70 ft) below the sea surface. ...
Source: https://en.wikipedia.org/wiki/Sea_surface_temperature

These are the average water temperatures of the Sea of Cortez over the year:

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Source: https://en.wikipedia.org/wiki/Gulf_of_California#Temperature

The bay north of La Paz is one of the collection areas.

Now, these fish are found at depth between 5 m and 25 m (16 to 82 feet), which puts them clearly above the thermocline.
That means the surface temperatures roughly apply to them.

In essence, these fish should be able to handle temperatures between the extreme low of 18°C (winter/spring) and the extreme high of 30°C (summer/fall), given that all other conditions are optimal.

I think the ideal range to keep them is likely between 20°C and 22°C in winter & spring and between 24°C to 26°C in summer & fall.
With these fish a seasonal change in temperature is advisable.

So far my two handled 25°C daytime temperatures without complaints. During the night the temperature drops to 22°C.
 

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I've got 2 in one of my QT systems at moment thanks to this thread, lol.
Can't tell if they are both M, or F, or 1of each. They don't hang out, but they don't fight either. I hope they pair, cuz they will be going in my 860g and I'd like to see them together.

Been 1week, and they eat voraciously.
 
Addition to my previous post:

"...
In the southern part of the Sea of Cortez, the temperature of the upper 30' of water or so remains warm enough year-round (70° to 80s) to support tropicals and several varieties of hard coral. Below that depth, winter and spring water temperatures in the 50s and 60s freeze out the tropicals. From mid-summer through November, water temperature is 80°F or higher for as deep as sport divers would care to go.

During spring and summer, the surface water temperature rises, of course, but the big change is the lowering of the thermocline. This is a complex and uneven process. During a June visit, the thermocline was at 45-50'. Sometimes the change was gradual or of small magnitude, but on one dive we recorded a plunge of 16 degrees between the surface, at 76°, and a thick layer of 60° planktonic green gloom 50 feet down. Later in the season, the water is 80° all the way past 100'. (We've even recorded 84° water in October.)
..."

Source: http://www.undercurrent.org/UCnow/dests/MexicoPacificInfo.shtml

So they should for sure be fine with temperatures up to 27°C for at least a few months of the year. And that's already the upper limit for corals.
 
I've got 2 in one of my QT systems at moment thanks to this thread, lol.
Can't tell if they are both M, or F, or 1of each. They don't hang out, but they don't fight either. I hope they pair, cuz they will be going in my 860g and I'd like to see them together.

Been 1week, and they eat voraciously.

It is highly unlikely that they are both males - those would fight.
If they get along it's either a pair or two females.

Good luck and post some pictures or videos of them here.
 
I've now seen both of mine scratch on the sand. At first it was just the little one, but tonight I also saw the larger one do it.
But so far I can't see any other symptoms.
 
I found another picture of what seems to be a pair:

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They look like my two.
 

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Tuesday evening:

<iframe width="560" height="315" src="https://www.youtube.com/embed/RLywH4Zr5lI" frameborder="0" allowfullscreen></iframe>

The smaller on shows some interesting behavior (towards the end of the video): I have a small goby and 2 dottybacks in the next QT and the smaller of the blue spots always looks there. It looks like he would want to eat the goby. He even goes into position out on the sand. But it seems he realizes that he can't get there.

Wednesday was a hot day here and when I came home in the evening their QT was at 28 °C.
But they looked fine and it for sure didn't affect their appetite - they eat like pigs.

They are also busy working on their homes and moving sand from one side to the other.

Let's see how they do the next few days.

The next two weeks will be cold which will bring the temperature down to where thy should be for them in April.
 
Is it just an illusion ? Watching the video it looks like the big one has more throat folds or flaps than the smaller one.


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