nautilus feeding

[ngdo]

Forgive me if this has been covered elsewhere - I have read numerous threads and articles but have yet to see a decent discussion.

How much and how often should an adult be fed? I currently have one adult in a 120gal tank (previously housed several generations of sepia bandesis, now lowered temp to 65 - I also have added a spongeless canister with Purigen and Phosguard, just for a little extra protection as I am not confident in the survival of bacteria at lower temps!)

He readily accepts just about anything I give him - fresh feeder crabs ("mud crabs", I crush them immediately before feeding so he has an easier time getting the meat), minnows (keep these feedings to a minimum although they were the only food he would initially eat; I suspect he was in an aquarium elsewhere only being fed fish previously based on this habit), and most recently fresh shrimp from the market, soaked in seldom. He also ate a small star in the tank...

What I am trying to understand is if there is a possibility of overfeeding. He seems to happily eat one piece of food a day, only - despite the size. Whether is is a crab (relatively small amount of meat per animal), a minnow (we will call this moderate - fairly meaty bullhead minnows), or a market shrimp (much larger) - he will eat it in its entirety but will not take any more food.

I have read posts suggesting a once a week feeding is sufficient but not a whole lot else on the subject of frequency. Since he is eating daily, I will continue feeding him as such - but would appreciate input from other keepers.

Thanks!

 

[robyn]

Hi ngdo,

When I had Nautiluses in a research lab, I fed them thrice a week on a 1-inch cube of fish head. At a different location I fed them one shell-on shrimp once every two days, but the animals there were larger and the water slightly warmer (closer to your temp of ~18 deg C).

How large is your animal? I think you could certainly cut down the amount you feed without compromising the animal's health at all, and this will also slow down the growth - some people seem to think you can overfeed which makes the growing edge of the shell thin and fragile, and the body growth rate to exceed the maximum possible foe the shell. It's not clear to me how common this is, though.
A varied diet is a good idea - are you feeding the shrimp with the shells on? Calcium is important for proper shell growth, so feeding shells and bony, crunchy things is a good plan.

 

[ngdo]

He is about 6.5".

Okay - so at least I shouldn't be concerned when he doesn't want to eat! I consider him a rescue as he was randomly at a store (they didn't explain where he came from but clearly he wasn't intentional stock). The water was about 78 and he was under bright lights. I have always been fascinated by the nautili and had a 120gal with nothing in it (last generation of cuttles had died off), so took him home and lowered the setting on the chiller.

Yes - I feed him the shrimp and crabs with the shells on. I fed him some fresh squid from the market this morning which he went wild for - swimming around like crazy and diving. He ended up spitting it out which made me a little concerned but I am guessing he is just full from the last couple days.

He is fairly active and seems to be doing well. Submerging about 18", haven't seen him go any deeper yet. He also seems to have figured out the tank as he rarely bumps into the walls. Even if he gets in the return stream he controls himself and navigates without impact.

And of course... Obligatory disclaimer... I do consider him a "rescue", I knew I could care for him better than he would get anywhere else around here. If I thought taking him home would encourage the LFS to to acquire more I would have thought twice. I am an experienced octopus and cuttlefish keeper and have a well stocked live food only tank and spare no expense for any of my animals.

 

[ngdo]

Pics

 

[gjbarord]

Thanks for the post!

I wonder how these animals just "wind up" at pet stores. It's tough to see because most people are simply not equipped to deal with them, especially the pet store!

To echo Robyn, nautiluses not eating isn't necessarily a bad thing as long as it doesn't end up being weeks of non-eating.

There is no concrete data to support this, but I have heard of places giving too much protein in the diet and it resulted in some very strange shell growth. When the diet was changed to a less protein rich diet, the shell returned to "normal". I've seen a whole range of feeding strategies from once a day to once a week. No one knows.

The guy you have is definitely a juvenile so a little extra feeding will probably not hurt but I think you could reduce the feeding, will also reduce the impact on your bio load.

Please keep us updated and good luck.

Greg

 

[ngdo]

Yeah, I'm not really sure how he got there. But like I said - he'll get the best possible care I can give him, and definitely much better off here.

He definitely seems to be doing better and better in my tank though. Sorry the pictures weren't clear, we keep the lights pretty low in the office anyway and the tank lighting is pretty minimal.

Just in the few weeks I've had him, he is already submerging more and more. Previously whenever he took a piece of food he'd eat it on the surface, now he is submerging and eating (assuming this means submersion takes less effort). This morning I fed him three shrimp tails, trying to maximize his shell/calcium consumption.

I've also observed him trying to pull snails off the tank - will he actually eat them? Not concerned about the snails, just more curious about being aware of what and how much he is eating, and whether or not he is supplementing with some of our cleaning crew!

As far as bioload (for now) we have a large volume - and spongeless - canister filter attached with some Phosguard and Purigen (along with skimming). I added it just to make sure there weren't any fluctuations in quality while we were getting acquainted with him. (another thing sometimes people criticize for is the occassional use of cannister filters, but I've found that with minimal media and no sponges they only have positive impact when needed).

I will also probably add an additional sump to the system and move most of the live rock out of the display. I have some extra 60 gallon tanks that would be perfect, and I figure the system could benefit from the extra water volume.

Anyway - just already took that precautionary measure as I figure out the best feeding strategy, how my hermits / snails / brittles will do with the tank being cooler and making sure everything gets eaten and stays clean. Advice on ideal cleanup crews for his tank is also welcome!

Thanks again -

 

[ngdo]

(quick disclaimer)
The lighting in the picture is a bit deceiving - it isn't nearly that bright! The right side of the tank does have LEDs above it, but there is also a piece of fabric across the top of the tank which gives it additional dampening. The left side has no lighting.

But the actual update - didn't get my camera out in time, but he is submerging nearly to the bottom of the tank on his own now. I'm very happy about the progression.

Over the coming weeks I'll be moving the majority of the LR to a second connected tank so that the main display is mostly bare bottom. There is about 1" of sand right now, I'm thinking about adding another inch of dry sand (suggestions here?) to the display. There are a couple horseshoe crabs down there keeping things stirred up and clean. I had completely forgotten they were even in the tank, they somehow seem a lot more active as the temperature drops.

I'm also looking at some of the offerings on www.coldwatermarineaquatics.com - and thinking about adding some of their tunicates in the coming weeks. I keep polycarpa aurata in the angler, seahorse and cuttlefish tanks and have always appreciated their contributions to the water quality. Having read that copepods "may" be problems to the nautilus, would having heavier filter feeders be beneficial?

 

[ngdo]

Update -

After having him for a month so far, he is fully submerging and hanging out on the tank bottom without issue. His appetite seems good - fresh market shrimp (fed next day, enriching these with Selcon overnight!), feeder crabs every other day, and a bullhead minnow once a week (hey, gotta get rid of these somehow!).

He'll find the shrimp on his own on the tank bottom if they're in the right locations. I still have too much LR in the tank but should be rid of it soon (moving most of the LR to a 60gal on the same system).

I'm planning on planting codium as soon as the rock is moved and introducing a population of penaid shrimp into the tank (good cleaners, good feeders when they get some size).

 

[ngdo]

Does anyone have experience with getting a nautilus to hunt in captivity, and if so what are they preying on?

Watching ours frequently drop small crabs makes me wonder...