Of the many Moray Eels, Family Muraenidae, some are far more suitable for aquarium use than others... Most of the more than one hundred species are piscivorous. What's that sound like? Right, they eat fishes. Most of these and some of the non-fish eaters get way too big for home aquarium use... a few to several feet in length, tens of pounds in weight! What's more, along with being too big and nasty toward tankmates, the majority of Morays are strong, adventurous types, escaping all but the most secure quarters. What's a person in the mood for a moray to do?
Enter a few of the non-fish eating Morays; particularly the delightful species of this article's focus, the Snowflake Moray, Echidna nebulosa. It doesn't get too big, grow too fast, generally harass other tankmates (unless they're crustaceans...), and for the family, is quite active during daylight hours. Small wonder that it is the most commonly encountered species of true eel offered in the trade.
Amongst the most wide-ranging of moray species. Commonly found in the Red Sea, along eastern Africa throughout the tropical Pacific up to Hawai'i, down to Costa Rica, about the eastern Pacific of Baja, Mexico.
Typically to two feet in captivity and the wild, but recorded at thirty two inches maximum length.
Most Snowflake specimens are easy to sort through. They come in two distinct qualities: excellent and dying/dead. Really. The standard "check to see that the animal is eating" applies here, and avoiding ones with obvious troubles (open sores, behavioral anomalies), but otherwise the vast majority of Snowflakes offered in the interest are "good to go".
As with all marines you're considering buying, do look over prospective purchases for obvious damage, feeding response.
A small note re size at purchase. In recent years I have seen absolutely tiny Snowflakes (under six inches) offered for sale... I encourage you and the industry to "scale up" here. Buy ten inch or more specimens. The smaller ones are too easily damaged in the chain of supply IMO.
Irrespective of purchase size, this and all Morays' tanks should be as large as possible (a minimum of sixty gallons, even for small specimens) and supplied with plenty of "stable" cover. Let's expand on these ideas. Moray eels are often "out of sight, out of mind" to aquarists who own them. Hiding by day, more active when their owners are sleeping. For such apparently sedentary creatures, muraenids are "heavy-bodied" and consume good quantities of foods at times, with concurrent waste production. All this foraging, eating/mess-making takes up "capacity" as in volume of their living quarters.
The "stable" cover reference is to remind you of the need for hiding (dark) spaces AND the fact that such arranged decor needs to be "settled" in. That is, not subject to falling onto your aquatic charges. Either "wiggle" heavy rock, decor items till they're settling on "the bottom" (the tank base, filter panel, plenum screen...) or set it on their first, ahead of placing your substrate/s. Do this same sort of "wiggling" of subsequent materials stacked on top of this base to assure their sturdiness.
See below under "Behavior", "On Jumping Out", re the need for a tight-fitting "hole-less" cover.
Per the above metabolic mentions, filtration/circulation/aeration should be vigorous, over-sized. Protein skimming is almost always a "must" with moray eel keeping. Ditto with redundant aeration, biological filtration. Does this mean you can only keep a Snowflake in a "species tank" or Fish Only system? No, have seen this (and even very large Moray species) kept in reef set-ups... with provisions made to mount corals, other sessile invertebrates in permanent position, in upper areas of rock work, and careful attention to just adequate feeding, regular water testing.
This species and most of the Moray family are extremely tolerant of widely and quickly ranging water conditions. Nonetheless, NSW (Near SeaWater) conditions are best to aim for with their captive husbandry, perhaps with slightly reduced specific gravity (a few thousands less than 1.025).
Snowflake eel specimens are by and large "live and let live" re their fish companions, but not always. I have archived on our site (www.WetWebMedia.com) a few instances of "Snowflake treachery". Such is definitely not the case with crustaceans. Echidna nebulosa's diet IS mainly crabs and shrimps in the wild. They will assuredly eat yours in captivity. Other non-vertebrate livestock is in no danger.
Re Jumping Out:
Moray eels are aquatic Houdini's, seemingly able to get out of any/all containers. What is the price of freedom? Constant vigilance. Know that even after your eel has settled in, it can, will be exploring the surface of its system most nights, possibly leaving... I have seen footage of this species going "intertidal" at night, in search of tasty crustaceans...
Should you discover your moray out on the floor moving, pick it up with a damp towel, rinse it off (yes in the sink with tapwater) and return it to a marine system. Even if the animal is apparently dry, stiff, don't necessarily give up. Do rinse it, and return anyway... and observe to see if it revives in an hour or so. Have witnessed this sort of "resurrection" on several occasions.
I have yet to come across a Snowflake Eel that would not quickly take to feeding in captivity. Quite the contrary, all types of frozen/defrosted, fresh meaty foods (including chunks of fish) are eagerly accepted. A note re hand-feeding your Morays; don't. In fact, it is a good idea to keep an observant eye on your hands if/when in the Morays tank, while feeding any of your charges... as they can become very excited smelling food, sensing their tankmates behavior... and render very nasty (and easily infected) bites.
Though certainly not generally the first to "catch" infectious and parasitic disease, Morays, including the Snowflake do succumb at times to such. The former are almost always linked to poor water et al. captive conditions or collateral damage in shipping, handling... The latter mainly the result of infestation by their fish tankmates.
I have had go-arounds with other pet-fish writers, culturists, public aquarium staff re "remedies" involving muraenids. They are sensitive than most fish species to these treatments. Copper and malachite IF utilized MUST not be overdosed NOR treatment periods extended for these species. I know this from hard-won first hand experience, re-collecting Morays killed by "No COPPER" treated tanks in San Diego, and readings of other to-be-trusted writers experiences.
As Moray species go, the Snowflake is tops. I do wish the other nine species of its genus, Echidna, made their way into pet-fish markets more often. There are a few of these that are similarly beautifully marked, easygoing toward fish tankmates, and stay relatively small.
Other than eating crustaceans (not always a bad thing if you're looking to get rid of some pest species...) and jumping out there is little not to recommend the Snowflake Moray, should you be in the mood.
http://www.fishbase.org Echidna nebulosa
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