Here's some info. on keeping the jawfish from a past issue of TFH. I would HIGHLY DISCOURAGE you from keeping this fish, especially in the current tank you have setup.
"...the normal choice of tank in the stores has been in the 12- 18-inch range (front to back). When filled with LR in the typical fashion (stacked against the back glass), this usually leaves only a few inches of exposed sand at the front of the aquarium. THis has two probable effects. First, in the wild these fish are usually found in pairs, with two burrow approx. 2 feet apart. Their 'comfort zone' is impossible to recreate in such a small space. But there is 'double trouble' here. As we noted while diving, the burrows are rarely very close to larger reef structures or debris. The most probable reason for this would be to create an unobstructed field of view for a sufficient distance in which to detect and react to pred
ators. In such close proximity to major structures, their inability to creat this 'zone of observation' can reasonbly be assumed to be a source of stress, especially in the initial period after introduction to the aquarium.
"In observing jawfish in these kinds of tanks, they are most often found in large 'scrapes' excavated under the structure. While this gives them a physical layer of protection behind them, and is obviously adequate for their maintenance, it is far from optimal.
"As we have noted, the jawfish typically dig vertical burrows. In order to be able to do this when they are fully grown (4 inches), the sand bed must be deep enough to accomodate this. If the sand bed is too shallow, construction of the burrow will be abandoned and they will seek deeper sand. When they are unable to find sand of a suitable depth, they will resort to a 'scrape' under the nearest convenient structure, which is what we are trying to avoid. In order to ensure that the jawfish will be able to dig a burrow in the fashion they would in the wild and still have sand beneath them, a bed of 8 inches would be required.
"To give the fish some semblance of their natural world, 48x18x24 inches would be the minimum dimensions, which equates to a 90-gallon tank. Better yet would be a 48x24x24 inch tank, which equates to 120 gallons.
"The standard recommendation for the substrate required for the care of jawfish has been a mixed-grain sand with plenty fo coral debris mixed in to give it some structural integrity. WHile this is well suited to construction of a tunnel or 'scrape' under some structure, it does not truly mimic the conditions in which the jawfish live naturally... The sand should be the finest grain size....
"While this species is commonly recommended for reef aquariums, this might pose something of a problem due to the water movement recommended for many of these tanks. A large number of corals require high and varied current to thirve in our tanks but, as we noted while diving, in regions fo higher current this species is all but absent. The overall current should be gentle enough not to move the substrate but just strong enough to keep food particles suspended.
"So we can see that there are significant differences between the existing recommendations for this species and the way they really live... With some imagination on the part of the aquarist and careful selection of tankmates (gobies and small blennies), invertebrates, and possibly some gorgonians or sea fans, one could create a beautiful little Caribbean ecosystem with these fascinating fish as the centerpiece." --Adrian Marsden
