Nautilus, varios questions.

[Guitarra]

Hello, im new to cephs, but i have cared other species as well. Well at least if a snail counts as a ceph... in that case i have plenty of experience!

I have recently (2 months maybe), adquired a couple of Nautilus, Pompilus i think. And so far the seem to be doing well, i feed them shrimp, squid (they can eat that right?), fish and clam.

They are on a 48" long X 36" wide X 28" hight tank, arround 100 gallons right?, and we hope to move them soon on a bigger place wich will be a circular pond 60" wide 35" deep on the depeer spot.

But the one rarely go to "explore" down on the depeest part of the tank, (i know 28" stills not deep enought), it never gets below the surface, i was wondering if i might have air caught on its shell, could it be?, if so theres a away to take it out?, i read the only live on the biggest chamber of the shell, does that mean the shell can be broken on the half and it does not matter?, can i put coral glue on the broken part?, will it feel apart?.
Oh and something went out of it...
Brown...like a strip but crumpled like... Its it poo?

You can read im new at all
Well so i hope i can get a general advice on their care aswell.
Still im reading lot of articles with no information at all, seems like the internet its poor on Nautilus information...
Cheers!

 

[chrono_war01]

It seems that Nautilus in my local aquariums don't often really go and explore, preferring to sit under a ledge or just content to floating near the surface, not sure is it healthy or not though, hope you get a more detailed response from other members here

And welcome to the forums~!

 

[monty]

to TONMO. Hopefully some of the members who have kept nautilus can help you in more detail soon, but I can maybe help a bit. A Nautilus is supposed to have air in the inner chambers of its shell, so you really, really don't want to violate that. The animal is almost entirely in the first chamber, but it has a tube that goes back to the chambers to regulate the gas and fluid levels. It is sometimes possible for this to have problems, but it's never a good idea to crack or otherwise damage the shell. I think some people have addressed the buoyancy problems by adding weights or floats to the animal, but I don't remember if that worked reliably... Also, the animal has control over its depth to some extent, so it may just not want to go to the bottom. If it can move up and down completely submerged in the upper part of the tank, it's probably fine, but if it's floating with part of its shell above the surface, that would be a sign of problems.

It would probably be helpful for the experts to know what temperature your tank runs at, what filtration system you have, and so forth. In the wild, nautilus lives fairly deep, so it needs low temperatures (a chiller is recommended) and they prefer low light levels. Unlike most cephalopods, they tend to be scavengers and filter feeders more than hunters, so I would expect what you listed as food is OK... see the article excerpts below for details.

gjbarord, marinebio_guy, and Robyn all have experience with these animals in laboratory and public aquarium situations, and I think Cuttlegirl has worked with them a bit as well, so hopefully they can provide some more specific comments and questions. In the June 2007 issue of Tropical Fish Hobbyist there is an article by gjbarord and marinebio_guy about nautilus, they address some of the specific needs and recommendations. Here are some relevant excerpts:

The main focus in the feeding of nautiluses is to provide food that is high in calcium in order to sustain normal shell growth. The most common food offered to nautiluses in captivity is shrimp (with shell), squid, various types of frozen fish, and blue crab. Several different types of molts, such as lobster molts, have also been fed as enrichment food.

For the average nautilus (less than 6 inches), the aquarium should be at least 3 feet long, 18 inches wide, and 2 feet deep to allow the animal to move around freely without constantly bumping into the sides of the tank; however, when keeping multiple nautiluses or a single large nautilus, a bigger aquarium is required.

(so it sounds like your tank is OK, although maybe crowded with two.)

...it is important to have a large biological filter bed or sand filter. A protein skimmer is also recommended to help manage the large waste load.

In this regard, nautilus requirements are similar to those of other cephalopods, so the ceph care articles under the "ARTICLES" button at the top of the page that discuss filtration should apply.

Another important aspect of keeping nautiluses alive is maintaining the water temperature between 50F and 70F, using a chiller. For a more natural environment and to aid possible breeding, one can have the temperature gradually fluctuate between cooler and warmer temperatures over a 24-hour period.... there should only be enough light in the tank to view the animal. Actinic lights work well for this, as too much light can stress the animal

the other immediate suggestion from the article is that the upper half of the tank should be kept open (live rock should be in the lower half) so that the nautiluses don't have obstacles that they bump into as they jet.

 

[gjbarord]

Like Monty said, you need to find out if the nautilus is unable to move any deeper. During shipping, many nautilus will experience positive buoyancy for a time. There is no quick cure for this. Waiting for the nautilus to adapt to its new environment seems to be the best method.

There is always air, or gas actually, in the chambers but it is the amount of seawater in these outermost chambers that regulate buoyancy. A normal nautilus is neutrally buoyant and utilizes its siphon to move between depths.

My suggestion is to give it some time and it should recover fine. Can you explain in greater detail this brown strip you observed? Where exactly did it come from? I presume that other than this anomaly the nautilus is behaving normally and feeding regularly??

Greg

 

[robyn]

Let me second what Greg and Monty have already told you - disrupted buoyancy is a common side effect of trapping and shipping. In my experience some animals recover after several months, and some never do. As long as it is eating and otherwise behaving normally I think the best option is to leave it as it is. I would definitely not recommend puncturing the shell - as Monty said, the siphuncle is a tube of living tissue that runs through all the chambers - it functions to aid chamber emptying (by osmotic flow from the chamber into the circulatory system of the animal) as the animal grows and forms new chambers. So definitely cracking or damaging the shell, even if you patch it, will disturb the chambers and possibly leave the siphuncle vulnerable to infection.

The brown strip you describe sounds like faeces. The colour varies depending on the diet, and it is expelled usually as a strip. Sounds normal.

Whatever you feed your guys, make sure they are getting enough calcium. So give them whole fish if you can (bones in), and shrimp with the shells on, or consider adding a calcium supplement to the water, which from my experience helps maintain normal shell growth.

Nautiluses are deep water animals so they need a cool and dark tank. I keep mine at 17 degrees C, but depending on the subspecies they might be ok warmer (I have had animals from Vanuatu do a lot better at 21 degrees). Do you know where they were caught?

A dark tank is really important. They live almost their whole life in dark water, and bright light is not only a bit stressful for them, but prolonged exposure can damage the pigment in their eyes, making them blind. A red light would be fine, but daylight or flourescent should be kept minimal.

Robyn.