FAQs on Characoids/Tetras and Relatives Selection

FAQs on Characoids/Tetras & Relatives Stocking/Selection

Related Articles: Characoids/Tetras & Relatives,

"If you've got the time (and habitat), we've got the bier/tetras"

Tetra stocking-too many choices       9/25/18
Hello Crew!
Thanks in advance for your time. I have had a 20 gallon long with fluorescent lighting set up for many years. It has been a peaceful community tank. Due to some pretty intense circumstances in my life the fish all dwindled away and it is now only home to a ridiculous amount of cherry shrimp who apparently are thriving in this neglected planted tank.
<Easy to trade in toward new livestock likely>
Now that things have settled down I have been able to purchase a 38 gallon bowfront LED lit tank. I set it up and it is currently cycling with janitorial ammonia, I have hopefully fast tracked this process by using a mucky (in a good way) filter cartridge from my old tank and some rocks and plants and such. As of now the parameters of the new tank are these:
Nitrites-0
Nitrates-20
GH-75
KH-40
PH-7
Temp-79
Ammonia is reading at .25 however it comes out of the tap like that and I treat with prime so I am thinking it may be an ammonium reading, however I am waiting patiently, I know not to rush the cycle.
<Should be cycled w/ the NO2 and NO3 readings you're reporting... I think the NH3/NH4OH reading may be spurious>
So I intend to move the entire shrimp brigade over, (any suggestions as to how to get all the babies are appreciated) and break down the old 20 gallon.
<Net out most all, drain water down and SLOWLY and carefully scoop out gravel and place in the new system in scoop/batches>
I want to do a peaceful tetra tank. I love neons but don’t want to watch them die from NTD. So I would like to do a few schools of tetras that will work well. I live in Miami and there are “fish farms” here.
<Ah yes; how well do I know>
Basically giant cement outdoor tanks containing every fish you can imagine, so my problem is this- I have too many choices and I don’t know what to choose. The local fish farm has Rummynose, black neon, green neon, ember and gold.
<All these are good choices and would mix; but I'd limit the arrangement here to just two or three tetra species; add some catfish of choice, perhaps a show specimen or two>
They have many more but I think I’ve narrowed it down to these. I would appreciate any suggestions as to which ones would work together and how many,
<At least ten of each>
I’m assuming a few schools of 10 or 12 each. I really love the Rummynose but I’m not sure they will work with my parameters and the others.
<Should. All have been raised in local water quality I assure you>
Any advice is appreciated, I have researched every tetra but I’m overwhelmed by too many options/combinations. Thanks again for your time! It’s very much appreciated!
Marya
<Thank you for sharing Marya. Please do send along your further observations. Bob Fenner>
Re: Tetra stocking-too many choices       9/26/18
Thanks so much! Will keep you posted...
<Thank you. Hey have you heard/seen the Zamora Catfish, Auchenipterichthys thoracatus?
BobF>
Re: Tetra stocking-too many choices       9/26/18
I have not, but I’m going to check it out now!
<It's a beauty! A bit exotic, but does make its way into the petfish trade on a punctuated basis. BobF>
Re: Tetra stocking-too many choices       9/26/18
Interesting. Will keep an eye out.
<Ahh>
Re: Tetra stocking-too many choices       9/27/18
Ok Mr. Fenner I have a few follow-up questions....
<Let's go!>
I started moving the cherry shrimp over, assuming it will take a few days to complete the process.
<Good>
I went to the fish farm to get a plant and they had some black and white striped bumblebee shrimp, I got 3. They told me they are very sensitive but that they are ok with the cherries.
<S/b fine. Likely the same species. Like blondes/brunettes>
I checked wet web and in my haste couldn’t find a lot of info but I took the chance. So far so good, any extra info on these would be appreciated. So in the tetra choices I have, which ones are least likely to bother the baby shrimp?
<All will eat the shrimp when they're very small; but some should survive; and adults will be fine.>
I know there’s always a risk but in your opinion which are the best bet
Also I purchased a very large “mother” Amazon sword. It is so large it has flowers and baby leaves growing off the top, so big I had to fold it over to close the lid and this is a tall tank.
<Neato!>
What do I do to make the babies? Hahaha sorry.
<Pinch them off and plant them separately; or bend the stem down and plant it in the sand/gravel>
Thanks again, you are the best,
Marya
<Thank you for sharing Marya. BobF>
Re: Tetra stocking-too many choices       9/27/18
Great! Thanks again for your advice. I am still working on the process of moving all the shrimp and the Nerite snail, once they settle in I will head back to the farm for some tetras, I’ll keep you posted, thanks so much!
Marya
<Glad to share your adventure! B>
Re: Tetra stocking-too many choices       10/4/18
Hi Mr. Fenner,
So the update on the process is this: I have most of the shrimp moved over thanks to the help of my 11 year old daughter, who has taken the task on due to the $3 paycheck upon completion.
<Ah, the ole profit motive eh?>
And so most are doing well, I have lost a few, not sure why, maybe just the stress of the move since all parameters have remained steady.
I went to the fish farm and purchased 10 ember tetras and 10 gold tetras. They have been acclimated and are all doing well and tend to school as one big group. I was at first concerned about adding 20 fish at once however I am keepers by a close eye and parameters are holding steady.
So as I’m getting ready to leave the fish farm the owner approaches me to show me the fish he just got in and he shows me the most beautiful Galaxy Rasbora.
<Neat animals>
So my question is this: what are the chances I can add them to my tank?
<Likely very good; as long as they're not much smaller than the new Tetras>
If I bump the temp slowly down to 77? He says they are locally raised so that wouldn’t be an issue but if I bump the temp down to 77 will this mix work?
<Again; probably so>
Also if I that is a possibility is 6 enough or is more better?
<Six or more; yes>
Thanks again!!!!
Marya
<Welcome. Bob Fenner>

Green neon tetras for large tank question     5/29/17
Hello,
<Hi Andrew>
I am getting to stock my 120 gallon planted tank. It's been set up for over a year but so far only has shrimp and Otocinclus. The tank is heavily planted with plenty of stems and hairgrass, filtered by 2 Eheim 2217 (cleaned monthly) and receives a weekly water change (30-50%).
<I'd like to use the change water on my house plants>
The main fish will be a school of green neon tetras (Paracheirodon simulans). Tank mates will be 20 Corydoras similis, 4 Otocinclus, 75 Amano shrimp, and probably what will end up being 100 or more tangerine tiger shrimp (after breeding).
<Sounds good>
*How many tetras can I get while still keeping the bioload reasonable?* I'm not concerned with nitrates and phosphates (as it is I have to add some daily for the plants), but rather other dissolved organic compounds. I've
found minimizing these to be essential for planted tank health. I'd love to have a large number to see the social interactions at their best.
<Fifty individuals wouldn't be too many, and would make for a nice school here>
Also I run the tank at 74 degrees - is this too cold for them?
<Mmm; yes; as well as the other life listed... I'd raise this to 77-78 F. for all>
Many fish database sites seem to list a wide temperature range for this species.
<Tis so>
Thanks,
-Andrew
<Welcome. Bob Fenner>
Green neon tetras for large tank question /Neale      5/29/17
<<No real disagreements with BobF., but would remind you that this species is very Cardinal Tetra-like in requirements; as Bob suggests, middling to warmish conditions preferable to cooler low-end tropical (i.e., the
opposite to true Neon Tetras). Avoid strong currents, but ensure a good oxygen level by under-stocking the tank and providing steady but gentle circulation. Softer water also essential here; not necessarily mineral-free, but lowish, maybe 2-5 degrees dH, certainly no more than 10 degrees dH. Keep the pH between 6 and 7.5 depending on your ability to maintain stable water chemistry. Specifically, if you're using carbon dioxide fertilisation, for example, link this to pH, and perhaps use a commercial Discus buffer to ensure stable conditions. Green Neons (Paracheirodon simulans) have a poor survival rate in busy community tanks, so choose tankmates accordingly. Small foods, fed in frequent but rather small amounts rather than one feed per day probably best. Bob is spot on in
suggesting a big school is best here -- Paracheirodon simulans does not do well in the usual 6-10 specimen schools people often buy. Cheers, Neale.>>
Re: Green neon tetras for large tank question     5/29/17
Thanks for the information and welcome! What an honor to get information from the man himself, Bob Fenner.
<Hee heeee. Just a petfish kind of guy Andrew>
I look forward to interacting more with your site in the future. I only discovered it recently but quickly found
it to be a wealth of knowledge.
<Ahh!>
Wishing the crew a happy Memorial Day holiday,
-Andrew
<And you, BobF>

South American tetra tank (stkg. mostly) 12/29/16
Hi,
I have a few questions about making some changes to my tank. My current set-up:
My tank is about 10 months old. It is a US 29 gal.(approx. 100 litre?) tall bow front. I want it to be primarily for small tetras. I am lucky to have soft slightly acidic water straight from the tap. The substrate is a layer of organic soil (3") with a 1" cap of smooth sand. However, my plants (mostly Anubias) have not done well. I douse them every second day with
Flourish Excel, but this causes more algae growth than plant growth, although I do see new leaves coming.
<You do not need to 'feed' Anubias. Certainly not every second day! Anubias grow extremely slowly, and nine times out of ten they'll get all the minerals they need from the tap water and fish wastes. Possibly add a bit of plant food if you get one or two yellow leaves. But if growth is all green, don't feed! Simple as that. As you observe, any plant food you add
will be used by algae. Also note that Anubias need shading from overhead light, or their leaves get covered by algae. They don't seem as good at resisting algae as most true aquatic plants (Anubias naturally occur in bogs and marshes rather than underwater).>
The lighting is OptiBright 24"" LED 15VDC, 0.5A max. My water temperature is minimum 78 F. My fish consist of
the following:
4 emperor tetras
9 neon tetras
3 checkerboard Corydoras (each about 3.5") <? RMF>
3 yoyo loaches (each about 3.5", and brought in to control an outbreak of pond snails)
The loaches and cories don't seem to bother each other; there are lots of hiding places created by terra cotta pots and driftwood, but the cories hide in daylight. I've lost a couple of dwarf rams, dwarf gouramis, and a school of rummy nose tetras mostly from an outbreak of Ick.
Much as I love the dwarf rams, I now I just want to concentrate on peaceful schools of tetras.
<Understood.>
My questions:
1. Are my loaches and cories too big for this tank?
<Borderline. While they're unlikely to overload the filter, Yo-yo loaches in particular are boisterous and active, so I'd certainly be keeping an eye on them. I'd also want to add a few more Corydoras, because the loaches might push them about a bit otherwise.>
2. Is my school of emperors too small; would they be happier with another four?
<Yes.>
3. Can I mix Neons and cardinals, or am I better to double the school of Neons?
<They actually prefer/need different conditions. Neons are from cooler areas, so their correct water temperature range is 22-24 C/72-75 F.
Cardinals are hothouse flowers, and really are happier around 26-28 C/79-82 F. While you might split the difference and keep them both at 25 C/77 F, I suspect you'll find Neons rather shorter lived than you would like.
Cardinals are generally less plagued by disease than Neons these days, and tend to live longer, assuming you have soft water and keep them reasonably warm.>
4. I'd like to reintroduce a school of rummy nose tetras. Are these four species of tetras compatible, and would you recommend as the total maximum load for this tank?
<I think you'd be pushing your luck a bit with these. They're highly social, and you really need at least a dozen for them to school properly, and they're also very sensitive to poor water quality. They seem to do better in spacious tanks where they can swim about freely. I'd be looking at either X-Ray Tetras or 'False' Penguin Tetras (actually the default Penguin Tetra of the trade) if you wanted something stripy and easy to keep. Both of these species are tough and undemanding.>
I don't think I'll pursue any more submerged plants; just keep those I can keep alive, increase the bog wood, and possibly add a floating plant, though I don't want anything that takes over.
<Amazon Frogbit would be ideal.>
Thanks so much for your advice.
Christine
<Most welcome. Neale.>
Re: South American tetra tank 12/29/16
Thanks so much, Neale! What a great service you provide!
<As volunteers, we're always pleased to know our help is useful and welcome. So cheers, indeed! Neale.>

A question for Mr. Neale Monks, Cardinal Tetras sys. (hard water) (Bob F., maybe you know better?) <<>> 8/29/12
Dear Mr. Monks,
I have been reading up your article about hard water in freshwater tanks:
http://www.wetwebmedia.com/fwsubwebindex/fwhardness.htm
This following passage caught my attention: "Dissection of neon and cardinal tetras has revealed damaged kidneys in specimens kept in hard water aquaria."
That cardinals and neons do best in soft water was part of my "basic knowledge set" of aquarium keeping, but an online forum I have stumbled across recently have very "respected" posters claiming that because they have managed to keep cardinals alive for 6 years in hard water showing nice colours, it proves that cardinal tetras do just fine in hard water.
<<Eugene; what is stated as "hard" water... alkalinity, GH, KH...?>>
This of course goes contrary to much of the advice given and data that is often thrown around in literature, online or otherwise.
Could you perhaps help me out in this discussion by citing the source of the findings of the dissection? It would be of great interest to me to dig deeper and enrich the admittedly superficial knowledge I have as an "ordinary" aquarist.
Best regards
Eugene
<Hello Eugene. I read the mentioning of the kidney problems in Cardinals and Neons from an aquarium encyclopaedia of the 80s, but I can't remember which one! I'm on vacation at the moment so can't look at my collection of books to try to find the quote. But a quick look on Google Books reveals a few mentions of the "calcium salts in the kidney" problem with regard to Neons and Cardinals, for example in Baensch's Aquarium Atlas 1 and a copy of Tropical Fish Hobbyist magazine from the mid 80s (vol. 35, but can't tell which issue). This latter suggests the calcium salts were spotted by one biologist who dissected the fish (the source is mentioned as one "Dr Schubert" there) and then informed the author of the TFH magazine article.
I don't have this magazine so can't read the whole article. Likely this "factoid" has been repeated by other writers thereafter, as in Freshwater Aquarium Models by John Tullock, first published in 2006. I haven't been able to find anything specifically about this problem in the modern scientific literature, though I haven't spent much time look either! But with that said, a little time spent using the search terms "Paracheirodon" and "hardness" on Google Scholar reveals some interesting papers, such as a short paper called "The red neon, Paracheirodon axelrodi (Schultz, 1956), is able to survive in distilled water" that reports not only that the Cardinal can survive in pure water for significant periods of time but breeds best when spawning takes place in pure water! In any case, I believe that the poor survival rates of Neons these days has less to do with water chemistry and more to do with their poor quality and often poor care at all steps in the retail and hobby chain. Neons can certainly do well at moderate hardness around the 10-12 degree dH mark, which would be about pH 7-7.5 in most cases. But Neons are bred to a price rather than a quality, overstocked on farms and retail tanks, sold as beginners fish, and usually kept much too warm all along the chain (they prefer cool water, 22-24 C/72-75 F). Neon Tetra Disease may be a real threat in many cases -- it certainly spreads very rapidly if infected fish are not immediately removed -- but many sick fish seem to be suffering from opportunistic bacteria rather than the Pleistophora parasite, in which case environmental stress is surely a major factor. To be honest, I stopped recommending Neons many years ago. On the other hand, Cardinals are largely wild-caught,
<<Considerable numbers are now captive produced... have seen many millions in Singapore>>
and if kept in warm, soft, acidic water are not difficult to keep and should live for 3-4 years without any problems at all. Hope this helps, Neale.>
Re: Question and comment re A question for Mr. Neale Monks (Bob F., maybe you know better?) Cardinals, hard water 8/31/12
Thank you both for your help.
<Welcome Gene>
<<Eugene; what is stated as "hard" water... alkalinity, GH, KH...?>>
The claims come from somebody who kept Cardinals in KH 6, GH 14 water.
<Mmm, moderate...>
He keeps telling me because they lived for 6 years, the conclusion is that they do fine in hard water.
<I'd agree>
The magazine Mr. Monks makes mention of "captive bred strains" of P. axelrodi in the USSR, that they seem to be more resilient in this regard.
<And to this. Those bred/reared and shipped through Singapore appear to be fine in harder water>
I am in Berlin, Germany, and the ex-East Bloc is just a stone's throw away, literally (Berlin wall and so on) - my local fish dealer told me that he gets his Cardinals from the Czech Republic, but is not sure if they are wild-caught imports or captive-bred.
<I want to make the comment that the last 10--20 years shows at
Nuremberg/Nurnberg, have shown many fishes, plants, live foods cultured in the Czech Republic>
Could it be that the Czechs are carrying on the "tradition" of successfully breeding Cardinals?
<I would not be surprised at all. In fact there are some Net reports of such:
http://www.seriouslyfish.com/species/paracheirodon-axelrodi/
http://www.aquaticquotient.com/forum/showthread.php/59249-Wild-Cardinal-Tetra>
Best regards,
Eugene
<And you, Bob Fenner>

Tetras for South American Cichlid tank 1/2/12
I am wondering if there are any suitable tetras for my South American Cichlid tank.
<Many.>
I currently have some Silver Dollars but kind of like the idea of a large school of tetras instead.
<There are quite a nice variety of Silver Dollar-type things. Have you looked at Myleus schomburgkii? This is a schooling species with nice colours and a maximum size of about 12 cm/5 inches.>
My current setup is a 120 gallon tank stocked with 6 Severum, 8 Eartheater cichlids, 6 Pictus catfish and 1 Rhino Pleco. I was thinking of Buenos Aires tetras but reading thru the FAQ I seen they can be fin nippers.
<And subtropical, too.>
Could you suggest a schooling fish that won't fin nip and is big enough to exist with my cichlids. Thank you for the wonderful site!
<Congo Tetras and Bleeding Heart Tetras are two others that would work and are widely traded. Cheers, Neale.>

Neon Tetras And Serpae Tetra, incomp. 5/5/08 Hello there, nice to be back! I have my problem with my 9 neon tetras and 5 Serpae Tetras. First week after I buy the Neons the Serpaes are not doing anything to the Neons, they don't disturb them. <Yet...> Yesterday I saw one of my Neons has no tail then one Serpae attack the neon and bite the neon's tail. <Ah, there it is.> I'm shock when I saw it, and until now I can't imagine the worst thing my Serpae did. I think of possible solutions, and it came to my mind that if I remove the Serpae tetra (3 of them) will the aggressiveness will be minimize, I will just remain one male and female. Is it ok? <Nope. Serpae tetras, as I point out repeatedly here at WWM, are not community safe. They eat fins and scales in the wild, and also have a "feeding frenzy" behaviour that means they lunge at anything and everything when feeding. Mixing Serpae tetras with anything other than more Serpae tetras is not a good idea. Period. End of discussion. They're great fish on their own, but were the very first fish I ever kept way back in the early 80s, and I learned my lesson the hard way.> please give me the right solution. My tank is 10 gallons, planted, and an Amazon blackwater layout. <Neons need cooler water (around 22 C) than Serpae tetras (around 25 C), so aren't really compatible anyway. I'd get rid of the Serpae tetras, since a 10 gallon tank is too small for them. Keep the Neons, let the temperature drop, and if you want obtain some suitable tankmates for this sort of tank, e.g., Corydoras habrosus.> Hope you will reply soon. Thanks and more power! <Hope this helps! Neale.>

Tips for caring tetra... Tetra Sel. 3/14/08 Good day to all of you! I just want to ask about my new fish, the tetra. I have 2 serpae tetra <Mmm, these Hyphessobrycons tend to be a bit too nippy... Do read on WWM re > and 2 black phantom tetra that are now in a school. I want to add 6 neon tetra, but the problem is my aquarium is too small for those fish (4.5 gallons). Now I'm planning to buy a 10 gallons aquarium, do you think it's ok? <Mmm, better> And should I get more black phantom and serpae tetras? <These are best/better kept in larger groupings... in small systems like yours, of odd numbers of individuals> I also want to add dwarf Gourami in them. <Do read on WWM re Colisa lalia... http://wetwebmedia.com/FWSubWebIndex/dwfgsel.htm> By the way my aquarium is well-planted, and I use Tetra Blackwater Extract. Thanks, hope you will reply soon. I attached a picture of my aquarium any suggestion or comments is ok! God Bless! <Umm, a very nice tank indeed... Cheers, Bob Fenner>

Schooling Advice... Neon Tetras 2/10/08 I recently e-mailed you guys about my school of diminishing neon tetras. After hearing from you guys that Neons are poor quality most of the time in large stock and from my own experience, I think Neons are just too much of a hassle and a waste of money because of there very short longevity. Currently there is 1 dwarf Gourami, 2 blue gouramis, 1 gold Gourami, and 4 rainbow sharks in my 55 gallon aquarium along with about 5 remaining neon tetras. Here's my question though. What do you think would be a good schooling fish. I was thinking about tiger barbs, but if you can think of something better that'd be great. I plan to just put my remaining Neons up for adoption at the petstore as I did with my crayfish. Thanks for you help and advise. <Jonathan, given you were keeping crayfish with the Neons, I'd not be too quick to blame the Neon's demise on poor health. In addition, it is absolutely essential you eliminate environmental factors before apportioning blame. So do a pH test and a nitrite test, and check your filter is still working properly and not clogged up. Obviously if the water isn't that great, *any* new fish you add are likely to suffer. Fish that have been established in a tank for many months will often seem happy enough in such tanks because they've slowly adapted to those conditions. But any new fish will be used to the water quality/chemistry at the retailer's tank, and will get stressed or killed by being dumped in entirely different conditions in your tank. In any case, Tiger Barbs would be a poor choice for a tank with Gouramis because Tiger Barbs are fin-nippers. So to are Serpae tetras, Black Widow (Petticoat) tetras, and several other small characins. Read up on any species carefully before you make a purchase. I happen to consider Bleeding Heart Tetras among the best all-around characins: they are pretty, quite big, constantly chasing each other but completely peaceful towards tankmates. They are also hardy and too fast for aggressive or nippy fish to bother (mine live in a tank with puffers and have NEVER been nipped). Australian Rainbowfish are also very reliable choices, especially if you have hard water. Cheers, Neale.>

Re: community tank recommendation, tetra sel. -01/30/08 Thank you so much for describing your diamond tetras. I changed my mind and decided on green fire tetras instead. I am wishing for a happy and healthy home for all. Best regards, Stephanie <Cool. Enjoy your fish. Cheers, Neale.>

Another with stocking problems, Wrong Tetras For Cycling a New Tank -- 09/08/07 Hello, I did the right thing and did a lot of reading on the web. I did the wrong thing and listened to somebody who sounded like they knew what they were talking about in the store. I have recently acquired a 125 g tank. Since I do not understand H, I will tell you it is 5ft long and 2 ft high. It is decorated with driftwood and slate and I have been adding plants as I go along. I has been my intention to get angels at some point and perhaps a variety of the more placid chilids <Spelled Cichlids> (yes, I know angels are chilids too). So the tank cycling was competed with zebra Danios and I was ready to add another schooling fish. I knew tetras would be good as long as it was not one of the smaller varieties. So I bought a really, pretty larger tetra, 8 to be exact. Turns out I may have made an error. These darlings are Buenos Aires Tetras. I self defence, I would like to add that this particular variety does not seem very popular and is often absent in tetra lists. I did not know there was an aggressive tetra. Now of course I know my plants may be doomed and perhaps the "Angel Plan" if I keep these active fellows. However, I have also read that kept in a group they tend to interact primarily with each other and leave others alone, thereby reducing the occurrence to fin nipping behaviour. What is your take on this? Should I express my unhappiness to the store and see if they can returned? I like them but hey, fin-nipping was not in the plan. Cheers Aileen <These tetras are like a pack of wolves and probably won't go well with any fish. I would recommend returning them unless these are the only fish you want in your tank.-Chuck>
Re: another with stocking problems. Aggressive Tetras 9/9/07 Hello again, And thanks for the quick response, it allowed me to begin to take action quickly. Sorry if I gave you the impression that these fellows were cycling the tank. They are not. The tank was cycled fishless but because I did so without either fish or a testing kit I ensured it was o.k. with zebra Danios for a couple of weeks. The tetras are in fact the second school introduced. The ammonia remained at 0 but in fact the nitrite did spike for again for a couple of days.......but everything is fine now, and was before the introduction of the tetras. I called the store yesterday when I got your response and they did not seem so eager to accept the fish, in fact the guy on the phone insisted that he had never had aggressive ones????? They might take to odd nibble from a plant but would not destroy them and if feed well and kept in a school would not bother the other fish. This too is information readily available on the internet. < These fish might be OK alone or in a small school. The larger the school the tougher the group. These fish are well known in fish clubs. They can be right up there with Exodon paradoxus. Don't let the word tetra fool you. Piranhas are closely related to tetras.> I feel like I am in a bit of a rotten position here, but really do not want to experiment. I am considering packing the troop up and going up to the store with them and regardless of refunds, leaving them there. What are the fair and responsible practises of stores in the fish trade? < As the store what fish you can place with your tetras. Buy something that you like and place it with the existing school of tetras. If the new fish get killed then tell the store you expect them to credit you with another fish that will go with the tetras, because they said they would go together. Eventually the tetras may or not kill most of the fish that they recommend. If they are smart they will take back the tetras and let you buy new fish.> Should they be expected to accept returns in this situation? < The aquarium hobby is very slow this time of year and they are probably glad to be rid of those fish. They will probably resist taking them back but I am sure they will take them for free. If you flat out don't want them any more then give them back and go to another store with more knowledgeable personnel.-Chuck>

Tetras, sel.... not pairs... -- 07/18/07 Hi guys! I recently bought a Von Rio Tetra (Flame/Fire Tetra) and a neon tetra, oh and an Otocinclus fish. I want to learn more about the Otocinclus but there's nothing on the web about them, and was wondering if you could help me with all the knowledge you guys have. Oh and I bought one of each with the tetras and found that they needed to be in a pair. Are they fine with each other and the community fish or do I need to get another one of each? And also can they mate with each other like Platies? Thank you so much! Derek <Hello Derek. First of all, you can't keep "a" tetra in most cases. These are schooling fish. Both Hyphessobrycon flammeus (the flame tetra) and Paracheirodon innesi (the neon tetra) are schooling tetras that should be kept in groups of 6 or more *of each species* i.e., 6 flame tetras plus 6 neon tetras would be the *minimum* number you could keep and expect them to last long and be happy. I don't know who told you they want to be in pairs, but that's rubbish. Tetras do not normally hybridise and being difficult to breed this isn't really an issue. Platies hybridise because the fish in the trade sold as Platies are all hybrids already of a single pair of closely related species. Now, as for the catfish, you're probably drawing a blank on your web searches because you're spelling the name wrong. Try "Otocinclus" instead. Several species are traded and retailers make no attempt to identify them. But they're all very similar. Otocinclus spp. are schooling fish that should be kept in groups of at least 4 specimens. They are herbivores, and green algae *must* be a major part of their diet. If your tank doesn't have enough green algae (and it probably won't) you need to add substitutes such as algae pellets, algae flake, or strips of Sushi Nori held in a "lettuce clip" (you buy these in aquarium shops, they're like plastic bulldog clips but with a sucker and used to feed catfish, tangs, cichlids, and other herbivorous fishes). Supplement this with sliced vegetables such as cucumber and courgette, plus small amounts of small invertebrates such as frozen bloodworm. Otocinclus spp. are delicate, and many aquarists have no joy keeping them. They need very clean, highly oxygenated water. Nitrite and ammonia must be 0 and nitrate as low as possible. The water temperature should be moderate, no more than 25C/77F. Hope this helps. Cheers, Neale>

Hemiodus goeldii/microlepis... insulting, cryptic note re Characoids 7/6/06 Hello, <Hi there> I read what you have on your site and found it to be less informative then I had hoped. <?> I was looking at a freshwater predator for a 55 gallon tank. I still have to setup the tank but wondered what kind of chemistry, tankmates, (if any) and foods, <...? for what species?> I have kept the needle nose gar as called on this page. Do they eat the same way? <In the mouth, out the... The two species/genus listed above "feed differently" in terms of approaching prey... grasping them...> The pictures show that they live in schools, <Hemiodus spp.? Yes> should I buy four, what is a good number for my tank? Thank-you in advance, Dan <A small odd-number would be better... 3, 5... Bob Fenner>

How Many Tetras? I would like to know how many tetra size I can keep in a 55 gallon aquarium? <It really depends on the type of Tetra as they reach different adult size. A good rule of thumb is 1-1.5 inches of adult size fish per gallon of water. Ronni>

FW Needlefish Well, we ended up taking the catfish back to PetSmart and getting 3 Bala sharks instead. I have one last question! We wanted to get a needle fish, we don't know much about them, but I heard they were very difficult to take care of. Do you know anything about them or have any advice? They seemed like a really cool fish to add to our tank. Amy & Chad <Not easily kept... need live food... and pretty large quarters... a tank three, four feet long... You can look up which species you're dealing with, its water conditions on fishbase.org Bob Fenner>

Neons vs. cardinals 7/21/05 Hello, wondering if I could get an opinion on these tetras. I'm planning on a 108 gal. community and want to have either neon tetras or cardinals as the main schooling species. What would be your recommendation with these fish for overall color, adaptability with other community fish and most of all hardiness? I know both require the same water conditions. That's it. Neons or cardinals? Appreciate any input on this subject?..........Regards, Craig P. <Mmm, am a big fan of both species, but will side with the Cardinals... for bigger size, greater longevity, relative hardiness. Bob Fenner>
Re: Neons vs. cardinals 7/22/05 Mr. Fenner thanks for your response and the cardinals sound good to me as well. I received a response from you on the Hagen lights for my tank last week; again Ty. I realized that your name was familiar and dug up one of my FAMA magazines from years past and found your article. Showed the e-mail I sent you to my son and then your picture and he was really impressed!! "Dad he's an expert", <Heeee!> were his words. He's 11. I've been in the hobby for about 10 years now and still enjoy it very much...... just ask my wife, lol. It's good to know expert advice is a click away.......... Thanks again. I live in the province of Newfoundland Canada and the hobby has really taken off here this past few years; both fresh and saltwater, but I find staff with any knowledge are few and far between. Anyway, I had to drop you this note to let you know, it's great to get advice from the "expert"..................... much regards.....Craig P. <Hmm, whenever I hear the term, I always think of "ex spurt"... as previously married and flow under pressure... Thank you, Bob Fenner>

FW Stocking, plant health, study Hello!! Your site is very informative but I have a question I have to ask: After cycling my tank want to have... 3 Platies 3 Corydoras catfish 1 Otocinclus or SAE <Interesting... different species as you know> 2 rams 3 harlequin Rasboras (maybe) 4 other tetras the tetras are where I want help. most of the fish I've mentioned are bottom dwellers. what sorts of small tetras can I buy to swim in the top half of my tank to balance it out. something colourful and not orange. <See WWM re... Perhaps some fish of the genus Hyphessobrycon...> Also, will my selection fit into my 29g tank? <Mmm, yes> another question, I have 2 plants, I think 1 is Hygrophila (not sure) <Can find pix of this, other aquarium plants... on the Net> and the other is a very fine leaved plant. anyway on the 1 which I think is Hygrophila, at the top the leaves are all curling up and on the bottom they are rotting. what should I do? I have the light on for 8 hours a day. <Read on my friend... Perhaps your water quality is unsuitable, maybe there is a nutrient deficiency at play here... perhaps your light quality is insufficient... Bob Fenner> Thanks in advance, James

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