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FAQs on Anableps, Four-Eyes

Related Articles: Four-Eyes, Livebearing Fishes by Bob Fenner,  Poeciliids: Guppies, Platies, Swordtails, Mollies by Neale Monks,

Related FAQs: Brackish Water Fishes in General,

A. Anableps       4/29/18
Hello Crew! I have been reading your articles and FAQ's on the Four Eyed Fish because that is the last fish on my wish list.
<They're certainly interesting fish, if rather difficult to keep.>
I do not have any of these fish now, nor do I have an immediate plans to get them, but I'm hoping, after the end of the irrigation season, October 15th, to get 4 of them.
I always do as much research as necessary before I get a fish, so when I was reading one of the posts on your site about an owner of A. Anableps who keeps 4 (I believe juveniles) in a 55 gallon tank (and it seems to be
working for her), it made me curious about their growth rate. I have an open 55 gallon tank and wondered how long a tank of this size would work.
Would 4 of these fish thrive in that size tank for a year or two?
<The species was first bred in captivity at Stuttgart Zoo, where the zookeepers determined their lifespan to be around 7 years. That being the case, I'd expect them to reach more or less full size within a couple of years, no more. You've also got to remember these fish are not only big (supposedly up to 30 cm/12 inches in the wild, but 20 cm/8 inches is probably more realistic) but also high social, and need to be kept in groups of six or more specimens. They're skittish too, so a big aquarium ensures they don't feel cramped. I don't really see 55 gallons as suitable for anything more than juveniles for maybe the first year. You wouldn't want to keep four, but at least six, and ultimately they're going to need something broad and wide like a pond rather than a tank. Even a large Rubbermaid 'stock tank' container could be used successfully! Anableps couldn't care less about decor or even water depth, but what they do want is a shelf of some sort just below the waterline that they can 'beach' themselves on periodically. At the Stuttgart Zoo they even had a sun lamp over this, and the fish all but basked under the light, much like a turtle!
Of course they don't want to be completely out of the water, but the shelf needs to be positioned so their body is covered but their eyes poking out above the waterline. Given the right conditions these fish are not impossible to keep, as a bit of reading online will reveal, but they are very specific in their needs. If I had a 55 gallon tank lying about, and wanted to keep something unusual, I'd be looking at something like Bichirs that are undemanding but bizarre, Polypterus senegalus and Polypterus palmas being my particular favourites. Both are a manageable size (around 25 cm/10 inches) and placid, so while predatory, they can be kept with L-number catfish, large characins, etc. They're also easy to feed, happily taking a wide range of frozen foods, even good quality carnivore pellets.
Cheers, Neale.>
Re: A. Anableps; and Misgurnis       4/29/18

That's exactly the kind of information I needed to hear - thank you! I love Weather Loaches and had 7 of them in a 125 gallon tank for two years.
Although I enjoyed them, toward the end I started feeling guilty because even a tank that big seemed too small for them when they all started swimming together. And, like the Anableps, Weather Loaches are social and need others of their kind around them. This year I was lucky enough to find out that one of the people that works at the aquarium store where I get my supplies had put a pond in his backyard, and he was very excited when I offered him my 10 - 11 inch Loaches. I still love Weather Loaches, but experience has taught me they are more appropriate as a pond fish than an aquarium fish and going forward, I intend to respect that. Sounds like it's the same with Anableps, so I think I'll find something else for my 55 gallon.
Thanks again!
<Most welcome, and glad to help. I agree with your observations of Weather Loaches, which make great pets by the way, and should be more widely kept.
They can do well indoors if given enough space, and are probably less demanding than things like Plecs and Clown Loaches, both of which get much too big for the average aquarium. Cheers, Neale.>

Re: Cichlids
Anableps (the thread formerly known as Re: Cichlids) -- 2/5/10

Thanks again Neale. I'm going to talk to the guy at my LFS about the F1 thing tomorrow. One more question, my friends Anableps, which is kept in brackish water, just had his fins turn black. Caudal and pectoral. He still eats and acts normal but I was wondering if you knew anything about it.
<Anableps can be difficult to keep. They are gregarious and nervous animals, so lack of company can be causing stress. It's also very important that they have places they can "beach" themselves. Do read my FAQ, below, and see especially the diagram of the habitat they need.
Cheers, Neale.>

Re: Anableps (the thread formerly known as Re: Cichlids)  2/6/10
Thanks. I'll give my friend the tip on the platform. It can't be anything about being lonely because he is kept with 2 Ropefish, a leopard Ctenopoma, and 4 Corys.
<What...? It's an Anableps, a brackish water fish. It WILL die kept in a freshwater tank. For gosh sakes, have your friend read up on what this fish needs. If the water is salty enough for the Anableps, these other fish would be dead. And "loneliness" in fish has nothing to do with OTHER species in the aquarium. Anableps need to be kept in groups of THEIR OWN KIND, not other fish. These aren't kids who're being picked on in school.
They're gregarious fish that need the company of other members of their own species to operate properly. Cheers, Neale.>
Re: Anableps (the thread formerly known as Re: Cichlids)  2/6/10
I'm not sure the exact chemistry of the water, but he says it's brackish.
<If those other fish are in there, and still alive, it's not brackish. End of story. Your friend obviously doesn't know what brackish means.>
It's the only Anableps in there too.
<It's a schooling fish.>
<I think we know why it's changed colour. It's unhappy and likely stressed by a poor environment. Have your friend read my book. Cheers, Neale.>
Re: Anableps (the thread formerly known as Re: Cichlids)
Thanks a ton Neale. I talked to the guys at the LFS about it and they said the same thing. I'm going to talk to him about it tomorrow.
<Glad to have helped. Signing off from WWM for the next couple days!
Cheers, Neale.>

Anableps anableps, sys., sel.    8/5/09
Hey there, my LFS has gotten a shipment of Anableps anableps in. I read the WWM FAQ on Anableps but have some questions.
<Fire away.>
a.) Are these actually primarily freshwater or brackish fish?
<Very definitely brackish water fish. Funnily enough, was at the London Aquarium yesterday and saw a whole bunch of them, the bigger ones with the Monos, Scats, Archers and Chromides in the mangrove pool, and the smaller ones in the Molly and Mudskipper tide pool habitat.>
b.) What end of the brackish spectrum are they on as far as salinity if they are brackish?
<Low to middling. They have evolved very specifically to move with the tide, and as you probably know live in very shallow water. Indeed, to succeed in captivity you need a just-below-the-waterline platform where they can rest with their bodies covered but their eyes poking out. I'd recommend something between SG 1.005 to 1.010 at 25 C.>
c.) Again if they are brackish would they be a candidate for possibly moving acclimating to a marine environment? (I have done this successfully with mollies and archer fish)
<Precise salinity probably doesn't matter much, but they cannot possibly adapt to a "reef tank" environment, so why you'd want them in fully marine conditions isn't clear me. Would strongly suggest sticking with the
salinity range described above.>
At the moment I have a freshwater tank and a saltwater tank (1.023 salinity) but don't have a brackish tank and unfortunately won't be setting one up most likely.
<Anableps absolutely must be kept in a tank designed expressly for them.
They are very difficult to keep unless you [a] get healthy fish and [b] acquiesce to their needs. Settled fish are wonderfully lively and will eat anything, greedily! But you will need to provide them with a spacious tank, good water flow, low to mid salinity brackish water, and a "table" in the middle of the tank where they can "haul out" like seals. (A sand bank works just as well, but takes up more room, so most folks go with the table arrangement.) At the London Aquarium the Anableps were resting in shallow pools that branched off from the main, deep pool, and it was instructive to see that the Anableps and the Mudskippers both exploited these parts of the display.>
I've read a lot of very wide varied information on this species ranging from completely freshwater to going to saltwater of 1.024 to breed and living on 1.015 brackish waters normally and would like any advice you may have on if I'd be able to keep this fish in either of my tanks!
<There are three species, two Pacific, one Atlantic, and to some extent there are differences between them; according to Fishbase, Anableps dowei being reported from marine habits whereas Anableps anableps and Anableps microlepis have not. So unless you can tell the three species apart, there's a problem right there. I'd recommend sticking to what's been established by the hobby as workable. If your retailer has some specimens, and they're a decent size, and feeding happily, would recommend snapping them up at once if you're at all interested. These fish are very rare in the hobby, and getting healthy specimens makes a huge difference, so reducing their exposure to freshwater conditions is critical. Cheers, Neale.>

Anableps photos   8/5/09
Hi Bob,
There was a message today about Anableps.
Attached, a couple of photos that might look good alongside the answers when posted tomorrow. One with two adults, and the other showing a juvenile resting in a shallow (inch or so deep) pool off the main tank. Larger, higher-resolution versions available if you need them.
Cheers, Neale
<Will post with credit to you. BobF>

Re: Anableps anableps   8/5/09
Went by there again today, he has three and to "show them off" he fed them flake, pellet, Mysis, and bloodworms and they cleaned house. It was insane how fast they gobbled everything up.
<Sound like great specimens! Healthy Anableps really are very active, greedy fish.>
I took one home but reading that they are a shoaling species I may go back for another, working on a positive ID right now.
<Good luck... species identity is based on the numbers of scales along the flanks. Impossible to do with live fish. For the two Atlantic coast species, this is from Ghedotti and Wiley:
1a. Scales large, fewer than 64 scales in midlateral scale row -- Anableps anableps
1b. Scales small, greater than 75 scales in midlateral scale row -- Anableps microlepis
Obviously impossible to do with live fish. Hence, much better to go with the average, and assume they need low-end brackish. This suits all three species equally well.>
These three have charcoal opaque fins which I don't seem to see commonly. In freshwater for the moment. The reason I'm asking about my saltwater tank (which is FOWLR and just a couple corals) is that it's much bigger and would better handle the space requirements of an Anableps.
<Won't work. For one thing, any corals and anemones will sting these fish. For another, the live rock will be too abrasive and covered with stinging or nippy animals. For a third, the salinity is all wrong. Just don't!>
Moreover it actually has a dock like area where the return pumps from the sump come in that I could easily add gravel or sand to. My freshwater tank has floating plants which he has already used as a floatation device but is only a 3 foot long tank. (SW tank is 4 feet by 2 feet)
<Just to recap: Anableps need very specific conditions to do well. You ignore these at your peril. You're after about 25% normal seawater salinity, e.g., SG 1.005 at 25 C. The tank needs to be fairly big, and a
flat table in the middle or along one edge will be necessary so they can rest. Don't add tankmates and don't bother with plants. The table and some sand at the bottom are all they need. They are demanding fish in some ways, which is why they are so rarely traded. Cheers, Neale.>

Re: Anableps anableps   8/5/09
PS. I've just expanded the Anableps section in my Brackish Water FAQ with a sketch of what an Anableps aquarium needs to look like.
There's quite a bit more information in my book as well as in two relevant Aqualog books, the Brackish-Water Fishes one, and the All Livebearers and Halfbeaks one. Any of these books would be worth either buying or borrowing via your local public library. Cheers, Neale.>

Re: Anableps anableps   8/5/09
Just thought I'd give ya an update. I've decided I really love these little guys so this morning I went out and purchased a platform with suction cups and have placed it below the water line so that the Anableps can crawl up and sit underwater with his eyes above the waterline.
<Very good.>
I've also lowered the water level so that I can see his eyes on the top from the front of the tank. The only other fish in the tank are a male Koi Swordtail and a horse faced loach.
<Xiphophorus hybrids tolerate slightly brackish water very well, as does the Horseface Loach, Acantopsis choirorhynchus, a species that naturally comes from brackish as well as freshwater habitats in the wild. Certainly does well up to around 1.003 at 25 C, possibly a little higher. So in the short term at least, this community of fish should work well.>
I'm going to very slowly start adding some salt to the tank. Hopefully not enough to agitate the other fish. Would you recommend
livebearer salt or actual oceanic salt like I use in my marine tank?
<Marine salt mix. In fact, if the nitrate levels of the marine aquarium are low (below 50 mg/l, ideally below 20 mg/l) you can freely mix "old" water from the marine tank with tap water to create brackish water as required. One part marine aquarium water to five parts tap water should get roughly the right salinity. Adjust by adding a little more saltwater or a little more tap water to get SG 1.003 at 25 C. Cheers, Neale.>

Re: Anableps anableps. Mormyrids, not brackish f' as well  08/05/09
Sorry to be a nag but I have one final question :) What is the salt tolerance of Peter's Elephant Nose Fish?
<Nil. They are textbook examples of primary freshwater fish with little to no tolerance of saline conditions.>
I do NOT have one but am interested in possibly getting one for this tank as well as a final tankmate.
<Good. Gnathonemus petersii, and indeed Mormyrids generally, are very difficult to maintain, and you absolutely must research their needs carefully before purchase. Do see here:
You're looking at a tank with a sandy substrate, no bottom-feeding competitors (like Loaches!), plenty of floating plants, and water of very good quality. Water chemistry isn't critical, but certainly shouldn't be
I am aware of their unique feeding requirements etc... and can satisfy those.
<Very good.>
Just wondering if you think they'd be able to handle this setup.
<Not really, no. In any case, suspect you'll have your hands full with the Anableps. If you want other fish, look at Mollies, Limia, perhaps Mudskippers (though probably not the super-aggressive P. barbarus).
Flounders/soles might work, but not with the loaches. Cheers, Neale.>

Anableps Update 8/6/09
Realize it's still very soon after our communication, however I've begun adding small amounts of marine water to the tank, gradually poured in a Dixie cup's worth of my 1.023 saltwater tank's water throughout the day yesterday,
<Do watch the salinity in the Anableps tank though... you're aiming for about 1.003 initially, perhaps 1.005 later on, depending on the tankmates.>
I also added a large floating turtle dock which I've fastened to the side and then weighed down with river rock until it's just below the service, the Anableps has already started making use of it.
<Very good.>
Just thought I'd give you an affirmation email for the information you provided me because as I'm watching him today his colors have changed from the charcoal opaque coloration to the normal translucent finnage color with
proper stripes on the side as they appear in pictures which I think indicates he's no longer in a stressed state.
<Good the hear.>
He is also happily gobbling up everything I've thrown at him including some live brine shrimp treats today.
Thanks for the advice so far he's really turning out to be a great purchase. Also I haven't tested salinity yet as I haven't added much, but my horse faced loach and koi swordtail do not seem adversely affected at all.
<Glad things are working out so well. Good luck! Neale.>

Anableps Species Questions - 02/17/03 Hi there.   <Hi -- Ananda here, answering the brackish fish questions...> I have asked you guys some marine questions before but now I have a question about a brackish fish (Brackish was for the longest time my most favorite type of fish and still ranks very high). <They are great fish -- I wish more people kept them.> I have had a 55G Brackish set up for quite some time now.  I have two Anableps anableps females in the tank.   <Very cool fish.> Two weeks ago I reordered some Anableps from our fw supplier at the LFS I work at.  They came in different than the true Anableps.  The two original girls have 3 blue stripes, while these two new girls have only two.  Also they swim much easier under the water while the true Anableps have equilibrium issues which forces them to make quick dives to retrieve food.  The two new girls have the split eyes but act differently than the trues.  The two new ones can lay on the bottom of the tank with no issue but can also swim with the upper eye above water like the other Anableps.  Also the two new ones are a bit more blue.  I first thought they might be the false Anableps but they supposedly don't have "four eyes" while mine do.  Do you know what the two new Anableps I have are?   <There are actually three species in the genus -- the other two are A. dowei and A. microlepis. You now have two out of the three species! I'm not sure which species you have, as there seems to be some disagreement between sources on which one is which. If you could send photos, we would love to see them! Please also consider sending a photo to the good folks at Fishbase.org, as they do not have a photo of this species (whichever one it is).> Also why is it so hard to get a male Anableps anableps?  I have religiously tried for the past four months from three different suppliers.  No one has them nor can get them.  I want one so I can breed them but so far can only get females.   <I've read that the females often school together, which makes the females much easier to catch for the pet fish trade. So your best bet for finding a male is probably from someone who's breeding them. I did a Google search and found at least one breeder's page; you might also check Aquabid and similar sites. I know of two stores near Chicago that occasionally have these fish. If I ever see any males, I'll post on the WetWebFotos boards.> Thanks for taking the time to read this.  Kim <You're quite welcome; these are fascinating fish. A bit more info, and bibliography, here: http://www.wetwebmedia.com/BrackishSubWebIndex/anableps.htm  --Ananda>

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