Jestersix

Considering moorish idol - requesting input

IOnceWasLegend

Frag Swap Coordinator
BOD
Wife and I were visiting a store yesterday, she saw the moorish idol, and we ended up discussing one as a possibility for our tank. I'm well aware of the reputation of these fish as difficult to keep, and - given we already have an established tank - wanted to solicit input before deciding one way or the other on if this is a 'doable' idea, or a terrible idea. Some relevant information:

1. Tank is a 72 x 30 x 21" IM Nuvo 200.

2. Current stocklist is 4 tangs (achilles, desjardini, kole, and a surprisingly chill powder blue), copper banded butterfly, 5x bimac anthias, bluestreak cleaner, watchman goby, bella goby, pearly wrasse, bicolor foxface, and banggai cardinal.

3. Fish would be sourced from, and quarantined by, Kenny, so disease/initial malnutrition is not a concern.

4. Fish would be introduced with the lights off, immediately after re-organizing some of the rockscape in the aquarium, and potentially with another fish (an exquisite firefish).

Thoughts, input, and success stories/warnings are welcome. Thanks!
 
I have heard very few success stories. I’m actually following a thread on humble fish about idols. Some people thought larger specimens do better than smaller ones.
There were some concerns about aggression and stress causing them to not feed. There were comments about tangs being aggressive towards them causing them to hide and not eat.
But given how poorly they do who knows what really is causing issues.
G
 
I remember there being a fish that looks like the MI, but isn't. From google, I got this

Some aquarists prefer to keep substitute species that look very similar to the Moorish idol. These substitutes are all butterflyfishes of the genus Heniochus and include the pennant coralfish, H. acuminatus; threeband pennantfish, H. chrysostomus and the false Moorish idol, H.
 
I remember there being a fish that looks like the MI, but isn't. From google, I got this

Some aquarists prefer to keep substitute species that look very similar to the Moorish idol. These substitutes are all butterflyfishes of the genus Heniochus and include the pennant coralfish, H. acuminatus; threeband pennantfish, H. chrysostomus and the false Moorish idol, H.
They are ver untrustworthy
 
I would love to keep them too, even as the only larger fish in my tank. Keep reading the limited content (real-life) for several months, and my thoughts are the following:
  • There seems to be a misunderstanding that them eating pellets is a great thing. Many seem to have accomplished this but these fish appear to still die suddenly even while eating regularly.
  • Hence the recommendation regarding fiber, as mentioned by Thomas. Elliot claims this is the key to their survival. And the food they are feeding. My favorite youtube channel (not) has this
  • Some people seem to have great success (7 years +) with a mated pair and believe is critical to the stress reduction. They are living in larger groups in the wild which is why they seems to need to be at least in pairs.
  • There is a dedicated Facebook site but hardly anyone posts there, which is not a great sign in my opinion…
  • Bringing them in after the tang gang is established seems to be the worst possible timing given their sensitivity to stress. Probably reason alone why our resident experts say instantly no.
To get this fish past the magic 1-2 year mark where most of not all of them seem to die appears to be not worth the effort.

In conclusion, the two fish I find absolutely stunning I will not have due to poor cost -benefit: this fish and the powder blue.
 
Clearly we need to give them more heavy metals!
PXL_20221226_224149392.jpg
 
I think I’ve seen aquatic collection sell “bannerfish” that look just like smaller versions of the idol and are supposed to be more coral safe and easier to keep. And cheaper. Look into that for sure if you like the look of the idol but aren’t married to that specific fish. @IOnceWasLegend
 
When I researched Heniochus, I learned that there are two different species that share the identical look. One is reef safe, one is not, but they are nearly impossible to tell apart and frequently mixed up when sold.

I decided to pass since I didn't trust myself or the LFS to identify which was which (they also get quite large). They are super cool though, and seems they are way hardier than the real thing. Just FYI in case you go down that route!

Edit - the two species are Heniochus Diphreutes and Heniochus Acuminatus, the former is supposed to be the desirable one that is "reef safe with caution."

Here's an old RC thread on how to tell them apart: https://www.reefcentral.com/forums/showthread.php?t=1626751
 
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When I researched Heniochus, I learned that there are two different species that share the identical look. One is reef safe, one is not, but they are nearly impossible to tell apart and frequently mixed up when sold.

I decided to pass since I didn't trust myself or the LFS to identify which was which (they also get quite large). They are super cool though, and seems they are way hardier than the real thing. Just FYI in case you go down that route!

Edit - the two species are Heniochus Diphreutes and Heniochus Acuminatus, the former is supposed to be the desirable one that is "reef safe with caution."

Here's an old RC thread on how to tell them apart: https://www.reefcentral.com/forums/showthread.php?t=1626751

IME both are not reef safe.
 
Although watching Elliot and Ryan it seems as if you get a healthy idol and feed them fiber-rich food this can be quite successful. Not sure if it is worth trying though, and corals will still be at high risk. It's a shame, a great-looking fish.
 
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