The Moorish Idol Thread

I spent some time with Idols in Tahiti and the only thing I ever saw them eat is sponges, and I closely followed them. I found a type of sponge growing wild on floating docks in NY that freezes well and Idols go crazy for it. In a few minutes in the summer I was able to collect a years worth to freeze. My Idol only lived 5 years then I killed it with a bunch of other fish in an accident so I don't know how long it would have lasted if it were not for that. My 100 gallon tank is also too small.
Also of all the idols I followed in the sea, they were all part of a mated pair.
 
While I do agree that sponge is their main source of food in the wild, I disagree that they will not survive without it.

I had my idol in a 400 G tank for 4 years before I killed it in a power outage. Lost all circulation and it and several other active fish basically suffoicated.

I fed my idol a varitey of pellet foods along with sheets of Nori. It was a fat healty fish. Alwyas swimming and seemed content.

As Paul alluded to, they need swimming room. They are very active fish and need the swimming room. Water quality is not as important as you make it out to be. Just keep the basic parimiters and they will do fine. I know my water quality is no where near some of the reef tanks that I've seen, but my fish are healthy and my corals are growing. Plus I was using NSW when I had my Idol which I beleive contributed to some of my tanks health, but thats a different subject. Unfortunatly, I'm back to mixing ASW now.
 
Hello everyone,

okay I need some help with my Idol.

I got one for my 220 G FOWLR for now.

I feed him brine, mysis and krill. he takes brine, but spits it out ! same with mysis ! (too big ? )

I soak all food in garlic for now.

I see it actively nipping the rocks and sponges and more.

Mr. Paul, can you advice me a war plan lol should I keep dumping vubes of mysis and brine and pellets in and hope it would take it ? any info/tricks are appreciated.

[I used to think I am good with fishes like this, till I tried this MI, been 2 days, and I am going crazy by his tank trying to get him fat :P ] (maybe I should relax and get away from the tank and let him eat :P haha)


thanks all.
 
Keep feeding your fish DJKMS.

The MI is eating real good now. I think he was a bit skinny when I got him and is starting to plump up now. He gets fed 3 times a day. 2 times NLS theraA pellets through the auto feeder and a mix of Omega Angel Marine & Rods. I do the omega because its first ingredient is sponge. I also picked up some Angel formula but those cubes dont seem to dissolve properly. My Idol also likes to munch on green palys and pipe organ. He is also constantly picking at the rocks.

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Good job Crusty Shellback and Paul! Your many successful years could have turned into growing old with Moorish Idols had it not been for the unlucky accidents. I've read all the posts now and still conclude that feeding sponges is necessary to keep them. I say this because Moorish Idols after shipping and handling are in a bad mood. When I'm sick or feeling bad I want comfort food and that is what sponges are to Moorish Idols. If they're not fed sponges a large variety of food must be fed to make up for the lack of sponge in their diet. Many times the fish won't even start eating these foods. So I ask, Does the Moorish Idol have a better chance of acclimating and living a full life with a diet of sponges vs. traditional food? The answer is yes! There are many people that look over this forum wanting a Moorish Idol and doing their homework. There are even more that want the pretty fish from Nemo named Gil and I don't blame them. The problem they'll have is hearing that it might be possible to feed normal food to these fish. It can be done by dedicated and extremely knowledgeable aquarists with mixed success. It would be better to buy a sponge and not worry as much if it will or won't start eating regular fish food(and if that food is providing its complete nutritional requirements). It's a continual eater like Butterfly Fish and a sponge provides food it can eat at it's own pace. There are many places that sell sponges and the average price is 30-40$. The sponge can divided and grown in 2 different spots. One piece in the tank and one where it can't be eaten and can be fed directly). Feed the sponge phytoplankton or oyster eggs which can be bought online. This may require the hassle of growing the phytoplankton yourself but it will complete the food chain for the Moorish Idol. The Moorish Idol in my opinion is the best looking fish and it has the personality to match. There also isn't a fish that stirs up more passion from us saltwater enthusiasts than this one. Feed it sponges because it's worth the extra effort.
 
Hello everyone,

okay I need some help with my Idol.

I got one for my 220 G FOWLR for now.

I feed him brine, mysis and krill. he takes brine, but spits it out ! same with mysis ! (too big ? )

I soak all food in garlic for now.

I see it actively nipping the rocks and sponges and more.

Mr. Paul, can you advice me a war plan lol should I keep dumping vubes of mysis and brine and pellets in and hope it would take it ? any info/tricks are appreciated.

[I used to think I am good with fishes like this, till I tried this MI, been 2 days, and I am going crazy by his tank trying to get him fat :P ] (maybe I should relax and get away from the tank and let him eat :P haha)


thanks all.

I recommend feeding small amounts and small pieces many times a day, even several times a hour. By many times a day, I mean 12-15 times. Just don't feed a lot at a time as that would increase tank pollution and the MI seems to shy away when there is a lot of food floating in the water. This will work. Just feed a few small pieces at a time. No need to feed more than it will take from the water column or that it will eat off the bottom within a hour. Just feed many many times small amounts and small pieces. You will need to keep doing this for 7-14 days but the fish should progressively eat more and bigger peices. If you work all day, then feed at least every hour when you come home until you go to bed. If the fish is eating, keep giving it more and more. You really can't make the pieces of mysis, brine, or scallops too small.

BTW, nori is very important but the fish usually will not immediately eat nori. However, when they finally start, they will always want it.

Good luck!!
 
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I am sure certain sponges are ideal for the MI. However, just like I can live for a very long time on foods that weren't around 10,000 years ago, so can a MI live on foods other than sponge. There are only 3 food groups, carbohydrates, proteins, and fats. A sponge does not have some mystical source of energy, vitamin, or mineral that has not been found in other foods. We do not know the nutritional needs of MIs (we know they eat sponge, but we don't know the nutritional makeup of the sponge), but I can tell you in our tanks they need to be fed a lot and always have nori available. My MI always looks best when nori is plentiful. Ironicly, I have not had my MIs eat nori immediately. Then take a while before they begin to eat it.

I have only bought 2 MIs and both have been very healthy. I had one for 4 years that died during a move when, as a result, my temporary tank set up was unstable and crashed. I bought my second 2 and 1/2 years ago and it is doing great. I gave this same advice about 7 years ago on a large MI thread that predated all these threads which I think was lost in an old server crash.
 
Outerbank do you have any suggestions to help get the MI to eat Nori? Maybe a soak or something? I have a sheet between 2 plies of bird netting. It has been in the tank a couple days now and im not sure the Idol knows its food. The MI eats everything else with gusto but I would like for it to eat nori as well.
 
Outerbank do you have any suggestions to help get the MI to eat Nori? Maybe a soak or something? I have a sheet between 2 plies of bird netting. It has been in the tank a couple days now and im not sure the Idol knows its food. The MI eats everything else with gusto but I would like for it to eat nori as well.

I usually cut green nori into squares about 2.5 inches by 2.5. I then fold it one way three times so it is about 2.5 inches by 3/4 inch. I usually feed 4-5 sheets of this a day.

I would just cut a 3/4 inch by 2.5 inch piece and place it in a nori clip, then in the tank about midway down. Place it in the morning and remove any uneaten at night. The fish will eventually start to eat it. As the fish begins to eat more, keep adding more until the MI can't finish it all. Mine have always prefered green nori. My MI keeps my yellow tang from eating much nori. With my first MI, I had a BIG powder blue tang and the PBT would really guard the nori. The MI was still able to eat nori, but I don't recommend agressive tangs with MIs for this reason. It can be done, but they will do better without being hassled. Of note, I did add that fisrt MI to the tank after the PBT was large and about 3 years old.
 
I can live for a very long time on foods that weren't around 10,000 years ago, so can a MI live on foods other than sponge.

Yes, if the fish recognizes it as food. As I said, in the sea, sponges is the only thing I ever saw them eat but of course they eat other things. I did not spend all day with them, only an hour at a time as my air always ran out before I learned too much.
I can collect sponge and they can eat loads of it, much more than you could grow in a tank. But I did not just give them sponge, I also gave them live black worms and they loved bananas. I am not sure if bananas is a good food or not but I guess they have the consistancy of sponge. I would first freeze the bananas then they were more "rubbery". Mine loved them almost as much as sponge. I also added Plaster of Paris to the bananas to add calcium and give it a thicker consistancy. It is hard to get the proportions correct but I smashed some bananna in with some dry plaster and added a little water. If you get the proportions correct it comes out the same consistancy as the sponge they are accustomed to eat. The stuff they eat in Tahiti is a lime green sticky stuff.
I have had many Idols and they all ate but as was said they all have a specific temperment and preference of food. I also gave them pellets soaked in fish oil which I supplied in a feeder a few times a day. I think I have pictures at the beginning of this thread.
I think that if I had a little larger tank I could now keep them indefinately but mostly because I could collect that sponge.
I would imagine that although they could probably live without sponge as Crusty has proved, sponge may have some nutrient that allows them to stay healthier.
Food is of course a combination of proteins and carbohydrates but it also contains other undigestable materials that may be needed for these fish. Parrotfish eat coral, even the hard dead parts but these parts are undigestible but the fish may get it's calcium this way or maybe it needs the fiber to digest other things, either way it eats coral for some reason just like a moorish Idol eats sponge. It could eat other things like many fish but for some reason it evolved to eat sponge and that is what it is supposed to eat.
We have great difficulty keeping these fish and in the thousands or hundreds of thousands of these fish that were collected for the pet industry, virtually none of them in a common household tank lived past about 7 years. I wonder why?
 
Hey Paul,
I'm still out here hanging on the edge. Haven't fallen off yet.

I'm still looking for my pair of MI's. Haven't found any yet. But I did get a nice pair of yellow head sleeper gobies. Wonder if they will mate in my tank?
 
Quotes from Rusty Old Shellback on page 7 and 8.


"One thing I've noticed about mine that is interesting is that he will not eat just any sponge. I have about 6 different types of sponges growing in my tank. Some he has completely devored and others he has not even touched. The others he just picks at every once in a while."


"I've also found him eating some of the sponges that grow wild in my tank. He will not eat all of the different sponges though, only certian ones. I try and keep some rocks with that type of sponge growing in my sump so that I can swap them out in the tank every once in a while."

Could you please provide a description of these sponges Mr. Shellback?

Food is most important piece to the Moorish Idol puzzle.
Environment is the second most important piece. (unaggressive tank mates, water quality and swimming space)
Social is the least understood, but that will come with time. They've been observed in pairs and would benefit from a mate. That's a hard one because of the stress they're under in the home aquarium. It's hard to tell the difference between male an female. It's not recommended to keep several of these fish together for space, territorial, and dominance reasons (except under ideal conditions involving very large tanks).

I know that spinach is good for me but I won't eat it if it's not in a salad. The Moorish Idol will need to be fed lots of small portions of nutritionally complete food that it finds palatable until a sponge replacement is found. Once they take a liking to a sponge they can be fed nutritious food and vitamins to round out their diet.
 
I thought I had poste dit in the thread somewhere but I'll recap for you from what I can remember.

First off, my tank is 7' long, 3' tall and 2 1/2' wide so it's a large tank. tank mates when i put the idol in were a pair of large (12") Naso tangs, large pink tail trigger, medium copperbanded butterfly, several yellow tangs, large blue hippo tang, gold flake angle and some small fish (less than 3").

I got my Idol from a fellow reefer because he had started to eat his prized Zoa's in his tank. I had a few Zoa's on a rock with some purple sponge and didn't care if he ate them.

When I got the Idol and placed him in the tank, he didn't seem shy and only my CBB seemed to take any intrest in him. He actually bullied the Mi a bit but the MI didn't seem to care. I contribute this to similar body and elongated nose that thye share. After just a few days of this, they seemed to be come best of friends and were almost always seen swimming and eating together in the tank.

As for the sponges, the MI did eat my few Zoa's and the purple sponge that was growing near it. He also ate some of the white sponge that I had in the tank. He never did eat any of the yellow sponge I had. There wasn't enough sponge in the tank however to support him and once he was accustomed to me providing his food, he seemed to leav all of the sponges alone.

As for food, I fed a large variety of just about every type of marine pellet that Dr. Foster and Smiths carry. I'd mix them all together in a large bucket and feed my tank from that. I also jad all sizes of pellets as I had small, medium and large fish in the tank. I only fed once a day with the pellets.

I had a few times made up my own mixture of food using a sea food medley I found at the local supermarket. This consisted of clams, squid, small octopus, shrimp etc. I mixed this in a blender with some broccoli, bananas, and selcon. I frooze this and would break of a peice every few day and feed the tank.

The other staple in his diet was Nori. I'd buy large packets of dried nori at the local Asian market. I just ha dto make sure I got the one without any added flavores, etc. All I ever did with the nori was place a sheet in the tank, my fish would take care of the rest. The sheet would usually last about 10 min in the tank as both my Naso tangs and Pink Tail trigger really loved it. But my Idol was not shy and would get in with the mix to make sure he got some.

An interesting observation I had with my Idol was that he was not shy. Whne I would go and clean my tank he never ran and hid. Even with my hands and arms in the tank near him, cleaning the front and side walls, it never spooked him nor did he run.

My tank setup was very basic. i used filtered NSW that I collected from our local university. I never matched temps when I'd put it in even though it was a lot colder than my tank. I'd do 50% water changes every few weeks with no ill effects. I added no supplements to the tank other than trying to run a calicum reactor. Which didn't work too good. Top off water was RO. I ran 400W MH DE bulbs on the tank.

If you click on my name, look at the pull down menu and click on my home page to see my build thread.
 
An interesting observation I had with my Idol was that he was not shy. Whne I would go and clean my tank he never ran and hid. Even with my hands and arms in the tank near him, cleaning the front and side walls, it never spooked him nor did he run.

I noticed this with my Idol as well. I can have my hand in the tank doing whatever and he just swims around it like no big deal.

One thing I did notice is my Idol is very sensitive to environment change. I recently got in a nice size SPS colony and had to rearrange a a couple of rocks in order to place it in the tank. This seemed to upset the Idol for a day or 2 as his coloration paled (most noticeable on the black bars). Needless to say I really try not to change around its surroundings anymore.
 
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You can't collect them in Rockville Center. I find them on City Island. They are all over the floating docks there. But you have to go into a marina like Minnefords or one of the waterfront restaurants. They grow about 2" below the water and are very common but not yet. They don't grow until the summer
 
Idol stressed? Why?

Idol stressed? Why?

Hi guys, so far so good I think. My idol seems to be doing really well, eating good, etc.

One strange thing I noticed though. I have LED's and at "dusk" when the lights begin to ramp down the idol goes to the back corner of the tank and paces up and down the corner of the tank. This type of behavior seems to be stress related but I cant figure out why. All other times of the day the Idol seems fine and stress free but when the lights begin to go down he paces. Any ideas?
 
I got my MI about 5 weeks ago into my 300g. I have read this thread and learned a lot. When I brought mine, he ate mysis at local store, and he was transition well to my system altough he was bully by my couple tangs. Now eats well, he eats my sponge at the tank, but he does not tough my yellow sponge too. I feed my fish with seaweeds with chopped sea fish from chinese supermarket, with some supplement of mysis.

I obversed my tangs doing back and forth like you described, and occationally my MI does too. I am not sure it is sign of stress. They seems coming out of it after a while.

Ming
 
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