Have you ever housed a...

[ejaustin]

I've been reading about some critters and I wonder if anyone here has had any of them and would share their experiences. Specifically

- Yellow-headed jawfish

- Sand dollars

I'm fantasizing about how to stock my bigger tank when I get one and I don't want these guys to get too set in the fantasy if I won't be able to provide what they need.

Thanks.

ej

[PeeperKeeper]

Sorry, can't help you there. I've never had either one. Wasn't there an article on RC about jawfish a while back, or was I just reading a long post about them? It seems like it was in that online magazine they have.

I didn't even know that sanddollars were in the pet trade. Have you actually seen them for sale, or were you thinking of collecting from the "deep blue"?

[xcreonx]

When I lived in Florida I collected sand from the Gulf for my tank. I sifted it carefully for any foreign items... bottle caps, hooks, etc... And placed it in the new tank.

When I tore it down 6 months ago after being up for 4 years, I found at least 13 sanddollars ranging from 1" to 3". I would see them every once in a while, but never knew I had so many. They must have come in as eggs or larvae or however they reporduce..

That being said, I wouldn't suggest them unless you were able to keep them in a similar habitat. They live in the sand in the Gulf, which was what kept them alive i my tank.

Gorgeous creatures!

[ejaustin]

Yes, there's a article about jawfish in one of the early issues of Reefkeeping magazine, which piqued my interest in them. But they require a *really* deep sand bed. (In the wild, their burrows are about 9" deep.) WWM says 3-4" is okay for them, but I was hoping for some personal experience from someone. I'm thinking about my dream tank, and if it's going to include yellow-headed jawfish, I'll need to make sure that I get one tall enough to allow for a sufficient sand bed for these guys. If you go with a really deep sand bed like that, I'm not sure what kind of maintenance it would require.

Let's say I got a tank that was 4 feet long and 3 feet wide. If I was going for a 10" sand bed, I'd probably want to go 30-36" tall. Would it be possible to partition the tank into areas, and then get 2 or 3 of these critters with one to a partition, let them build their burrows and establish their territories, and then take out the partitions? ( In the wild, their burrows might be as close as a foot away from each other.) If I can assign them sort of pre-defined territories like that, would it be possible to maintain a shallower bed elsewhere in the tank?

In my mind, the answers to all those questions are "Maybe" and "Need input!"

As far as the sand dollars go, I was thinking it would be cool to have a lightning whelk, since their remains are the state shell of Texas and they are left-handed. It didn't take much reading to convince me that there's no way I could provide for a lightning whelk. They get to be more than 12" long and they eat bi-valves, maybe exclusively, and really no one has a great deal of info about the lifetime rhythms of the lightning whelk.

I'm not sure which turns I took to get from lightning whelk to sand dollar, exactly. Maybe a site that has info on lightning whelks had something on sand dollars, too. Much more is known about sand dollars and they seem theoretically do-able. In this dream tank of mine, I'm currently envisioning the front of the tank having a stretch of sand, with the rock more toward the back. That way, I could devote some space to critters that prefer sand to rock (assuming I could find compatible species of each). The idea that they would be hidden most of the time, doing their own thing, is absolutely okay with me. But I don't see a lot of mention of them, so I thought I'd ask.

Basically, I'm doing a lot of reading and in my head I'm sort of populating the tank and figuring out what the aquascape would need to be for a given population. I'm thinking an area that has rock that goes pretty high and maybe having some zoos or maybe even corals of some kind, but I'm not really jazed by the idea of having a tank that is *primarily* coral. I find that I'm attracted to quirky and often hides-a-lot kind of critters.

In my tank now, the shrimp are the showiest and I enjoy watching them, but seeing the royal gramma hanging out on her veranda for a couple minutes just makes my night. The astreae snails are busy little guys who leave nice clean trails, but I'm charmed by the Nassarius snails who wiggle into the sand like a child getting comfy in a down mattress on a cold night and then levitate up through the sand as if by magic when I feed the tank. And I love watching the subtle changes on the live rock.

Sorry. Didn't mean to wax poetic.

Anyway, the information in articles is interesting and the retailers can be another source of some info, but it's not exactly the same as chatting with someone who's lived with one of these guys.

ej

[thedude]

I've kept yellow-headed jaws and will post on my experiences with them manana.

[Ed]

JimD has kept Jawfish also. Maybe he'll see this and chime in.

[jroescher]

I have a Dusky Jawfish, and from what I'm reading they seem to be pretty close to the same in thier habits.

My sandbed is about 4 to 6 inches of southdown covered with 1 to 2 inches of special grade aragonite. My jawfish can dig to the bottom very quickly. He has two different places that he switches between every few weeks, and occasionally lives in both at the same time. When he decides to switch places, the holes usually have filled back in. He spits mouthfuls of sand up into the water and the southdown turns my tank into a vanilla milkshake for the day.

He's fun to watch. The closer something gets to him, the more his mouth opens. The closer the snails get, the more nervous he gets until he finally grabs them and hauls them to somewhere else in the tank and spits them out.

When I feed frozen brine shrimp, he comes out of his hole and grabs the shrimp at the speed of lightning. I've never had mine try to jump out, but if he did I would never see it. They are very fast swimmers.

During the night, he comes out of his hole and cruises around, but never far from his hole.

Give him a bunch of rocks and shells about 1/2 inch in size and he'll build a wall around his opening.

[ejaustin]

Thanks for the images. How close can somebody get before the jawfish escorts them elsewhere? What kind of tankmates does he have besides snails and how do they get along? Do you think he's happy enough with the 4-6 inch sandbed? What do you think of the idea of trying to sort of pre-define a couple territorities with partitions for a while (I'm think a couple or 3 months) and putting a jawfish in each area? Do you think that would help them establish the boundaries in their own little heads and minimize the squabbling when the partitions are removed? (I'm thinking of a tank with a 3' x 3' or 3' x 4' bottom, with part of it devoted to sand and with rock in another part -- either in the back or possible as an island in the middle.) Where did you get the special grade aragonite for him?

Thanks for taking the time to share your experience.

ej

[thedude]

Ok yellow headed jawfish.... first off, they are serious jumpers. I would never keep them in a tank without a lid because they can and will jump out to carpet surf eventually. They are an extremely fast and jumpy fish and the slightest scare could send them rocketing out the top. I've lost two jaws that way.

I would go with a sandbed closer to 6 inches as they dig extremely deep burrows in the wild. I saw several diving in St. Croix and they live in open sand, and the burrow went down FEET as far as I could tell. I'd also be sure to get a sand from the Carribean that includes many different grain sizes. The only way they can successfully make a good burrow is with many different shell fragments etc. to use as braces. Caribsea sells a dry version and a live version. I think the live version is $30 for a 20lb bag and and the dry is $30 for a 30lb bag but I'd have to check to be certain. Note that the dry version has TONS of dust in it and must be rinsed before using.

Keeping a sandbed that deep I would include LOTS of nassarius snails to help with waste removal and turning the sandbed over.

Hope that helps,

John