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FAQs on Silver Dollars Compatibility

Related Articles: Serrasalmine Fishes, Piranhas, Characoids/Tetras & Relatives

FAQs on: Silver Dollars (Metynnis, Mylossoma, Myleus...spp.) 1, Silver Dollars 2,
FAQs on: Silver Dollar Identification, Silver Dollar Behaviour, Silver Dollar Stocking/Selection, Silver Dollar Systems, Silver Dollar Feeding, Silver Dollar Health, Silver Dollar Reproduction, Related FAQs:  Serrasalmine Fishes, PiranhasPacus,

Trouble with Red Hook Silver Dollar Cichlids... incompatibility      8/25/14
I have two red Hook Silver Dollar Cichlids that are in a tank with a Red Empress.
<Red Empress variety of Peacock Cichlid? May be a clue. These fish come from Lake Malawi and need hard, alkaline water... which your Silver Dollars don't. While there is a middle ground for them I suppose that might work -- around 10-12 degrees dH, pH 7.5 -- if your aquarium was set up correctly for the Red Empress, it wouldn't be a nice place for South American characins, and if dumped into this tank from one (e.g., at the retailer) where the water was soft could kill them quite quickly if they failed to adapt. So some information on the aquarium is essential to answer this question.>
Today they started mysteriously turning gray, swimming upside down, and then wedging on the side of the tank in a vertical position. Unfortunately they both died within a matter of an hours of each other. What caused this?
<Almost certainly something wrong with the environment. When two or more fish of the same species sicken and die at the same time or within a few hours/days, then the environment is almost always the explanation.
Something was toxic to them. Water chemistry could be a stress factor as mentioned, but also water quality. How big is this tank? Red Hook Metynnis (Myloplus rubripinnis) are large fish, up to 25 cm/10 inches in length, though 20 cm/8 inches would be considered large for aquarium specimens.
Either way, we're talking aquaria around the 300 l/75 US gal size, with commensurate levels of filtration. You also mention the fact you have two Red Hook Metynnis; do remember these are as much schooling fish as Neons, and keeping fewer than 5-6 specimens is asking for trouble. Another factor is diet. These fish are more or less entirely herbivores in the wild, and their diet must include some greens or at least plant-based foods (such as Spirulina flake). Overuse of meaty foods of the sort the Aulonocara like
will do them no good, potentially some harm.>
I did a water changed and all levels were fine so I'm confused and very upset.
<I'm confused too because you haven't sent any sort of data. Read, review and send along some information including aquarium size, what sort of filter is used, and ideally water chemistry and water quality measurements, not vague comments about them being "fine" because that's of no help to me at all.>
<Cheers, Neale.>
Re: Trouble with Red Hook Silver Dollar Cichlids     8/25/14

Thank you for your response. I will send you the requested aquarium information when I get home from work tonight.
<Cool. Glad to help. Neale.>

80 gallon, 3 Koi angel fish 3 silver dollars     2/13/14
Dear crew at wet web media, I have been crawling the net searching for my problems pictorially and advice wise, my param.s are
Nitrate 20 (In zone of a jungle 5 N 1 test strip kit according to kit safe)
<At the highest I/we suggest... See WWM re NO3, control in FW>
Nitrite 0
Soft water
Moderate alkalinity
PH neutral 6.8
Temp: 75
80 gallon
3 Koi angel fish
3 silver dollars
<Mmm, do "like" similar water conditions, but the dollars are too quick moving for the slow angels and vice versa>
Anyhow my tank cycled for 2 weeks, yes I understand now after the fact that it should have been longer, I do 2 20% water changes a week, my lfs is closing and I bought 3 Koi angel fish and 3 silver dollar fish. Upon coming home I noted one silver dollar fish with what looked like white paint brush stroke, not lines, not grains not cottony, along back top fin, and I have attached a photo, he eats normal seems good, before bring him home though, I noticed that in the tank at lfs there were tiger barbs, and they must have nipped him as he does have some missing finnage, what is this white paint looking stuff and how should I treat it.
<Looks to be some sort of physical trauma... likely a brush with a Dollar>
Nextly I have angel fish all seem okay but one, whom has been swimming up the side of the filter in the tank and up against the heaters, I moved it to a quarantine tank and it just sat on the bottom, it seems paler and to have a hallowed stomach, its missing one ventral fin, and swims pointing up a lot.
<The new tank... and the mis mix of species>
Another of the angelfish (mind you all of these came from one huge tank at lfs angels and dollars) it seemed like he had 2 raised scales? It was hard to say just like orange bumps hardly noticeable and a few missing scales. I have attached photos thank-you for all your time and consideration.
<And this... IF I had two tanks, I'd be separating. Bob Fenner>

Silver dollar and E. Blue Jack Dempsey? Comp.?     8/24/12
First off, I love your site. It's an invaluable tool for any fish keeper.
Most of what I've learned over the years has either come from here or been reinforced by your site, especially as it pertains to reef tanks. I've read about all I can here regarding my freshwater question and can't quite find a definitive answer.
<Let's see if I can help>
Right now I have a 29 gallon with 2 small black moors and about a 4-5 inch silver dollar that I rescued from a bad situation. I know this arrangement is hardly ideal, but everyone gets along. It has an AC70 fully loaded and another smaller power filter with some floss just for extra mechanical.
It's heated to around 78 for the silver dollar's benefit and the goldfish don't mind.
<Agreed. Fancy goldfish are fine at this temp.>
NH3 is zero, NO2- is zero and NO-3 never surpasses 40
<I'd keep under 20 ppm>
or so with water changes. Everybody is happy for now. But I've always known the arrangement wouldn't be permanent.
So I purchased a used 46 gallon bowfront in hopes of setting up a tank for the silver dollar with more of his kind and other proper tank mates. The problem is that of course the tank came with what I'm pretty sure is about a 5 or 6 inch electric blue Jack Dempsey. I have him in a holding tank until I get the tank set up properly.
<I see>
Is there any chance of these two fish living peacefully together?
<Mmm, maybe... w/ enough room to maneuver... and the Dollar being introduced first... a few days to become familiar... they might get along. I give the situation about a 50:50 chance>
Or is the cichlid going to have to go with other cichlids only?
<Mmm, maybe not even this/these>
I don't want to take much of a chance with the dollar's well being. I've already nursed him back from bad shape once. The dollar is very submissive, presumably from sharing space with the boisterous yet well-intentioned moors. The Dempsey also seems rather unagressive, at least to the extent that I've observed him thus far. He had shared his tank with an Oscar until it died when the owners moved. He spends all of his time under his little tree-cave. I suppose all of this previous behavior can go out the window when certain species are mixed.
<And certain individuals>
I suppose another option is to simply rehome the Dempsey to someone that knows what they're doing. I've always wanted a cichlid tank but I really hate to have to build around one fish and not have options about tank mates. I always pictured my cichlid tank with Mbunas.
What do you think my options are? What would you do?
<Maybe try mixing the two... with a plan to trade one or the other in... longer term, another tank/system>
I patiently await your sage response.
<Sage as in the herb I take it. Cheers! Bob Fenner>

silver dollar tankmates 2/23/11
Dear Crew,
Congratulations on your great job and keep up the good work! I have a 55 gal with 2 overhead filters running. The inhabitants are 6-3" silver dollars (hypsauchen) and a 5" Featherfin catfish. Can I still add some more fishes? If yes, what would look best? A cichlid? Small schooling fish perhaps? What kind?
Thanks a lot
<Hello Carlos, and thanks for the kind words. Silver Dollars in 55 gallons is a bit of a squeeze, and wouldn't ever be my recommendation. Potential cichlid companions for Silver Dollars include such things as Severums, Chocolate Cichlids, Festivums and Blue Acara in soft water, while Rainbow Cichlids, Firemouths and Honduran Red Points should work in harder, more alkaline conditions. More oddball choices could be things like Fire Eels, Tyre-track Eels, Bichirs, Climbing Perch and Pristolepis spp. Cheers, Neale.>

Will different silver dollar species school together? 7/28/10
Hi Crew - I have 4 spotted Metynnis (spotted silver dollars) and wanted to add a couple of normal silver dollars to add variety. Will they school together?
<They'll get along, but there's no guarantee they'll school together. A good rule of thumb is to keep no fewer than five of any one Silver Dollar species. Any fewer and there's always a risk of in-fighting and dominance issues. Of course, your own mileage may vary, and the size of the tank makes a huge difference. Cheers, Neale.>

Damaged Silver Dollars; Gobioides broussonnetii in the wrong tank   1/16/10
Hi I have two silver dollar fish with red anal fins.
<Likely the Red-hook Metynnis, or something similar.>
we have had them now for 3 months now and never had a problem , but today I discovered that almost all of ones fins are missing and the other looks like little bites are taken from them.
<Well, two things. Firstly, they can be nipped by other fish. Tiger Barbs and Red-eye Tetras (Moenkhausia sanctaefilomenae) are on the potential list of biters. You've actually made things worse here by keeping these in insufficient numbers; barbs and tetras should be kept in groups of 6+. In smaller groups even the best species can become nasty. It's like getting a potentially lovely dog but then keeping it cooped up indoors all the time.
With the best will in the world, that dog will become frustrated and aggressive. Same thing here. By keeping these fish badly, you've created the conditions for social behaviour problems. Secondly, your Silver Dollars need to be in a bigger group as well. They are extremely social fish, and in small groups their social behaviour goes haywire. Yes, you've guessed it, this can manifest itself as aggression; in other words, fin-nipping.>
I watched them for a few minutes, and saw only one other fish taking interest in them and actually peck at them.
<Problem identified. What are you going to do to fix it?>
the fish was a bleu speckled platy and it is much smaller than the silver dollars I'm not sure of the type of platy it is blue with dark specs on it. are these fish known for such things,
<Some are, yes. But even "good" fish can become nippers when bored or frustrated.>
or do you think the silver dollars have other issues. I have a 80 gal tank and its clean the filter is a fluvial 304.i know there should be more dollars in there but I don't think that's the problem.
<But I think it may well be, and I've been doing this for a LONG time. So hear me out...>
and they have never showed any aggression towards each other there are about 27 other fish in there
2 tiger barbs
<Nippy; 6+ specimens.>
3 sword tails
<Males are aggressive.>
1 Danio
<6+ specimens; can be nasty when bored.>
3 angel fish
2 blood fins
<6+ specimens>
2 red eyes
<Nippy; 6+ specimens.>
3 gold fish
<<Need to be elsewhere RMF>>
2 African butterfly
1 6 inch dragon fish
<If this fish is Gobioides broussonnetii, and I think it is, it's a BRACKISH water fish and is doomed to die in a freshwater aquarium. Surely you didn't buy such an unusual fish without reading up on its needs first?
Either you did that, which was bad enough, or you ignored the advice you'd seen about it, which is even worse! Cannot be kept with any of these fish, except perhaps the Guppies, which will do just fine in a brackish water aquarium at the requisite SG 1.005 (about 9 grammes marine salt mix per litre). Note that adding a teaspoon of salt per gallon will not help one bit; adding enough salt for this Goby will quickly kill all the other fish in this tank, except for the Guppies.>
1 blue platy
3 pearl gouramis
1 blue Gourami
1 fire tail guppy
all these fish are much smaller than the silver dollars except the dragon but its totally non aggressive.
<Indeed. Gobioides broussonnetii is a lovely fish. It's a shame it's so often bought by people who insist on not researching its needs prior to purchase or decide for whatever reason not to keep it the way it should be kept.>
Any help would be greatly appreciated.
<Up the numbers of the fish being kept, removing surplus fish as required to make space. Transfer the Gobioides broussonnetii to a brackish water aquarium.>
please and thank you in advance
<Happy to help. Cheers, Neale.>

Silver dollars not eating   5/13/09
<Service to you!>
I have a problem with silver dollars not eating. In three weeks they have only eaten once, as far as I can tell.
I have a 90 gallon tank with an 8 inch Oscar, 6 inch cichlid of some kind,
<Oh! These might well be psychologically malaffecting your Dollars>
who are both doing well, and 3 silver dollars. Yes, I know I should probably have at least 6 silver dollars, but I do not.
<Three are fine here>
There is an established pecking order, with Oscar on top and dollars on the bottom.
The dollars do get pushed around but are not really attacked or bitten, just chased a bit.
I have not turned a light on over the tank at all since they have been here. I do water changes weekly, and I change the filter components as specified. The filter is overhanging, said to be good up to 110 gallons.
<You really could use more... Much more here>
I raised the temperature a couple degrees recently, only because one web page mentioned it may help (although I didn't really believe it would) - the temp is usually at 75 but now up to 79, using one heater.
<I'd use two here... and hide from the cichlids>
I have had the dollars for 3 weeks and they have only eaten once. They have ample opportunity to eat, as I distract the other fish while attempting to feed the dollars (Oscar loves to hang out with me). I have tried floating flakes and pellets, like they were fed in the pet store, as well as sinking cubes of thawed omnivore food ( a mix of brine shrimp, plankton, veggies), beef hearts, krill, and even hand picked and chopped earthworms. They simply ignore the food as it floats in front of their face and sits on the bottom near them. I plan on getting a floating live plant, in the hopes they will munch on that. My guess is the Oscar will tear it apart but who knows. I cannot feed them at the surface as they seem to be more scared of me than the other fish. They are usually swimming about when I get home from school, but hide in the corner when I am in the room. They looked healthy when I bought them, seemed to adjust well, ate for the first time a few days after I put them in the tank, but have not eaten since. They still look relatively healthy, but show signs of deterioration. One seems more pink-ish now than silver, and kind of seems to have his head caving in.
<A very bad sign... of starvation>
I would love to keep them, but they seem to hate their life. Any ideas on how I can entice them to eat?
Meghan Moran
Masters Graduate Student
Crop Science, University of Guelph
<More a matter of incompatibility than feeding here. These S. American Characoids need to be placed elsewhere... Apart from the "terrifying" cichlids... Another co-factor might be water quality... They do prefer even warmer water... and soft, acidic conditions as well... But do move them to another system in any case, and soon. Bob Fenner>
Re: silver dollars not eating 5/13/09

Thanks. I got that done...borrowed a tank, set it up, had the water checked, got the go ahead to transfer the dollars.
<Ah, good>
Sad state of affairs indeed. I hope they recover, then I suppose I'll have to find someone to take them. Thanks for your time
Meghan Moran
<Thank you for this follow-up, and caring, being human to make this prompt change. BobF>
Re: silver dollars not eating 5/15/09

Thanks. Your response made me feel a bit better. I feel guilty and I feel terrible for the fish. The first day in quarantine and they didn't eat. Any special way to entice them or particularly tasty treat that would be irresistible?
<Yes... palatable plant material... something like
Egeria/Elodea/"Anacharis" and warm water (low 80's F)>
Now I also noticed the Oscar has Ich, must have just set in/become visible.
My problem is the quarantine tank is in use! Would being in a Rubbermaid bin or other such plastic container stress the Oscar out if he can't see out of it?
<... See WWM re... I'd just raise the temp. where the fish is>
I don't know what to do, I don't have a third tank. How long does it take to treat the Ich?
<... See...>
I'm sure that length of time can vary.. I just feel awful about this whole thing, I want them to be healthy.
Meghan Moran
<I want you to use WWM. B>
Re: silver dollars not eating 5/15/09

You're right, usually I check all the articles first. Thanks for your time :)
Meghan Moran
<Ah, good. BobF> 

Cichlid in need of help
Parrot Cichlid Getting Intimidated By Silver Dollar  4/14/09

Hello, My name is Suzanne. I have a cichlid that's in need of help. He's bright orange (solid color, no spots), about 4 inches long- I don't know what type he is.
< He is called a parrot cichlid. This is not a true species but a cross.>
We've had him for approximately 3 years and he's never been sick.. until now. Our cichlid has lived alone in well- taken care of 46 gallon tank for the last 2;5 years. About a week ago, we introduced two silver dollar fish, which the people at the aquarium store recommended. The cichlid and the silver dollars were fine for the first few days. A bit of fighting.. The cichlid jabbed the silver dollars in the eye. Our cichlid got a torn fin. I've been putting "Melafix" into the water to speed up the healing process. But the real problem started about 3 days ago. One morning I woke up and the cichlid was lying upright (meaning not upside down or sideways, just upright, except not swimming) in a shell that was recently placed in the tank. He has been lying in that shell and hardly ever leaving it ever since then. When I approach the tank, he comes out, swims,
and looks fine overall. His color has not changed, he has an appetite, there are no strange spots (except a very miniscule black spot on his head). When he swims, at times he seems absolutely fine.
Other times, it looks like he's putting a tremendous amount of energy into swimming, but he doesn't seem to move very far. It even looks like he's twitching sometimes. Very spastic. Other times when he leaves the shell (which is rare), he hangs out on the floor of the tank and eventually, starts looking unsteady, and veers onto his side momentarily. Inevitably, he returns to the shell and stays there.
I'm not sure, but he looks like he's breathing heavy. It's hard to tell. The silver dollars seem absolutely fine. They're swimming around and look very healthy. They're not bothering the cichlid anymore at all. They pretty much leave him alone when he comes..
maybe approaching him a bit, but it doesn't seem particularly aggressive.
We checked the water levels. The pH, nitrite and ammonia levels were fine. The nitrate levels were slightly elevated. We changed 1/3 of the water, cleaned the filter (but didn't clean/change the little cylindrical pieces in the filter, or the pellets- to not over-clean), suctioned the gravel, and changed the air pump so that now the bubbles it generates are considerably stronger than before. The water temperature is at approximately 89 degrees.
< Way too warm. Lower to 78-80 F>
He looks completely catatonic, although again, there don't seem to be any other obvious signs in terms of his color, appetite or otherwise that indicate illness. Is it behavioral? That seems crazy.. but it crossed my mind
that perhaps he feels really aggressive towards the other fish and is avoiding them. Or could it be his fin that's bothering him? Or is he really sick? Any advice/suggestions/resources would be a tremendous
help. Thanks so much. Suzanne
< Thanks for the photos. They were very helpful. The silver dollars have ganged up on your parrot cichlid. He is now very stressed and may have an internal bacterial infection. This cichlid cross does not defend himself very well and is easily picked on by other fish. If the silver dollars are removed he may swim normally. If the silver dollars are removed and he's still has a swimming problem then there probably is an internal infection.
You fish will not get better with the silver dollars in there. Once they are removed treat with a combination of Nitrofuranace and Metronidazole. This may cause some ammonia spikes because the antibiotics may affect the biological filtration.-Chuck>

Re: cichlid in need of help
Cichlid Intimidated By School Of Silver Dollars 4/18/09

Hi Chuck, I just wanted to thank you for your advice. I removed the silver dollars right away and bought the recommended medicines in case there was a need for them. The Silver dollars have been out of the tank for
less than 24 hours, and our parrot cichlid has already begun to swim around and is looking much more active. I'm not sure yet, but I think it might have been just what you suggested- severe intimidation. I'm
keeping an eye and seeing how things progress before I introduce the medicine. Thanks very much again! (By the way, I typed the wrong temperature of the tank when I wrote to you initially. The temperature
was in fact around 78 degrees.. thankfully not 89 degrees!)
All the best, Suzanne
<Glad everything worked out ok and no medication was needed.-Chuck>

Re: Silver Dollars I really want to put aquatic plants in my 55gal but I have 2 Silver Dollars that ate the previous plants I have tried. Do you have any suggestions on a particular species that may not taste good to them?. <Some of the tough Anubias species might do here... and the less palatable Java Moss, Hornwort/Coontail (Ceratophyllum) might be worth trying... otherwise, you might consider building a divider blocking access to the plants (keeping the Silver Dollars separated). Bob Fenner>

Silver Dollars I recently converted a 60 gallon tank from salt to fresh. It is currently in the process of cycling.   <Sounds good!> My ultimate goal is to have a school of silver dollars, accompanied by a couple schools of smaller fish such as neon tetras.   <Ultimately, the silver dollars will grow large enough to happily gobble up Neons....  Though they are primarily vegetarians by nature, lunches-with-fins are still lunches-with-fins.> My question is this, assuming I have 8 small 1" fish in this tank, what is the largest school of silver dollars that my tank could support.   <Well, considering that silver dollars top out around 5-6 inches (depending upon what species you get), I would consider than any of those 1" fish would be at risk of being eaten.  But, assuming that they don't, and everyone lives peacefully, and you're not talking about 1" waste factories (baby goldfish, baby Oscars, etc.), I would think three or four adult silver dollars would be comfy in a 60 gallon tank.  While small, you could try more, but you'd have to watch for aggression and thin them down as they grow - and they do grow pretty swiftly.> Thank you for your help.  Dane Sure thing.  Wishing you well,  -Sabrina>

Silver Dollar Compatibility Good day ladies and Gents, I have two Silver Dollars (Metynnis hypsauchen) that have outgrown my tank. They've been together in my tank for two years now. A friend of mine has a 75 Gallon with a mated pair of the same fish, and he said he would gladly take them. I looked through the FAQ's and did not see an answer to my question so I feel safe in asking it.. :) I was just wondering if they're would any aggression between the pairs, and if the tank is large enough? Thank you as usual! Heather <In all likelihood these four will not only get along, but be much happier in a larger grouping... this is how they live in the wild. Bob Fenner> 

Hatchetfish, Silver Dollars, Discus, Compatibility - 05/19/2006 Can one keep Hatchet Fish, Silver Dollar, and a few Discus fish in a 55 gallon tank? <I would not mix silver dollars and discus.  Discus are typically shy and timid, silver dollars are boisterous and perhaps too fast/aggressive.  The discus would likely not get enough to eat in this mix, and would get pretty stressed out.> What do I need for setup if possible?   <Research, mostly.   http://www.wetwebmedia.com/FWSubWebIndex/fwsetupindex.htm > pH?  Ammonia?  Nitrate?   < http://www.wetwebmedia.com/FWSubWebIndex/fwestcycling.htm , http://www.wetwebmedia.com/FWSubWebIndex/fwph,alk.htm > No plants if possible.  Thanks  -Mark <Wishing you well,  -Sabrina>

Fishy Mystery From A Forum Reader - 03/08/2006 I got your email address off the WetWeb website. I have a question and am not a member. <Feel free to join the forums; it's free and fun!> I have 3 silver dollars, I have a 47 gallon tank with a few platies, mollies and tetras. I had a 5 inch rainbow shark and he disappeared as do some of my platies and mollies from time to time. I think when my fish die the other fish eating the body, as sometimes when I clean my tank I'll find something that looks like a skull or fish skin. The man at the fish store said silver dollars are aggressive, I've never read anything bad on the internet about silver dollars. What do you think? <About what, the silver dollars?  Or the mysterious disappearances?  Silver dollars CAN be aggressive.  I very much doubt, though, that they'd be able to take out a sizeable critter like your rainbow shark minnow.  They tend to be a little harsher on plants than fish, but smaller guys like little platies and tetras may get munched.  As for the dying fish, yeah, it is VERY common for active, healthy fish to try to eat a dead or dying tankmate, so that's what's happening with the bodies - the mystery is, what exactly is killing them?  The answer here may be something in terms of water quality.  Please be testing ammonia, nitrite, and nitrate; ammonia and nitrite must be ZERO at all times; nitrate less than 20ppm.  If this is not the case, correct it by doing water changes until the levels are right.  Make sure you use a chlorine/Chloramine neutralizer and match the temperature and pH to that of the tank.  Wishing you well,  -Sabrina>

Temperature Range - Metynnis and Rams? Sys., comp. - 09/30/2006 Hello y'all, <Hi.  My apologies for the delay in reply; I've been out, and your email came to us in a format that unfortunately our Webmail system had some trouble with, and I am one of the only folks able to respond to it.> First of all, thanks as usual for your maintenance of a wonderfully informative site. <Thank you very much for these kind words.> (I recently wrote my comprehensive exams for a PhD in education, and cited this site as a great example of a constructivist learning environment. So thanks for your contribution to my degree as well.) <This is high praise indeed - thank you again.> I would like to keep Metynnis hypsauchen and Microgeophagus ramirezi together in a 150 gallon system. <Maybe possible in this size system, given enough plants and hiding spaces....  but do keep in mind that the rapid schooling and darting about of the Metynnis may be stressful to the shy rams.  This is something I, personally, wouldn't try, but I imagine it can be done with success in as large a system as this.> My plan is to keep the temp at about 80-81° F, as this seems to be at the upper limit of the silver dollars and the lower limit of the rams. <The rams can go lower if you don't intend to breed.  Warmer would be preferable for them, but I'm rather concerned about the warm water making the Metynnis even MORE quick and spazzy.> However, I'm concerned that much of the literature about rams stresses that they're delicate, and happier at temps around 85. <Indeed.  But I would not bring the Metynnis to this temperature.> Should I: a) go with the "intersection" temp of 80-81 b) keep the temp higher, on the theory that the silver dollars are more tolerant of out-of-range temps than the rams c) not keep the two species together? <....  I would choose "C".  But again, that's just me.> Thanks again for your help and patience. <And you, again, for your kind words and consideration!> Melinda Johansson <All the best to you,  -Sabrina>

Guppies tails being eaten  -- 07/01/07 Hi, we have a 60 litre tank with several tetras, 2 Silver Dollars, 6 Platys (with a week-old baby in a net cage!) & one Clown Loach. A few days ago we acquired 4 Guppies which we assumed to be male due to their colourful tails. All was fine for the first 2 or three days then, one morning, we found a severely traumatised little person minus tail! We quickly separated him from the others but he died shortly after. We noticed that one of the other Guppy's tails had been nibbled, though not to a great degree, and kept an eye throughout the day. However, yesterday morning, he too had died. Whatever's happening seems to be doing so during the night. Might you be able to advise as we find it so distressing & feel we've done something awfully wrong. Many thanks, Don & Jenny. <Greetings. As you perhaps realise, a 60 litre (16 US gallon) tank is too small for silver dollars. Silver dollars potentially over 10 cm (4") in length and are exceptionally active and fast moving. I'd hesitate to recommend them even for a tank two or three times the size of yours. Clown loaches are schooling fish, and should be kept in at least a trio. Keeping a single specimen isn't very fair to the fish, and you'll probably find it is shy and nervous. Clown loaches are even bigger than silver dollars, and definitely need a bigger tank than yours. For a trio, even a 200 litre tank would be too small. So that's the analysis of your livestock over! Almost certainly the guppies are being nipped by the tetras. Silver dollars generally aren't nippers, so I'd cross those one of the list. But Serpae tetras, black widow tetras, flame tetras, and a few others are regularly implicated. So if you let me know which tetras you have, we can try and identify the culprit. In some cases the problem is too few members of the school, but in other cases the tetra concerned feeds on skin and scales in the wild, so is simply doing what comes natural. Either way, mixing tetras and fancy guppies is almost never a good idea. Even Neons have been known to nip fins under such circumstances! In the meantime, treat for Finrot/fungus. Cheers, Neale.>

Reply... Neale, Don & Jenny... Silver Dollars...    7/2/07 Hi Neale, many thanks for your reply and advice. Our Silver Dollars are about 3-4 inches and seem quite happy. Our Clown Roach 2-3 inches & also seems happy. He/ she is out and about quite a lot from under his log. We intend getting another as we had 2 to start with but one vanished overnight some weeks ago!- but haven't been able to locate a small one. We have a few Neon tetras, 5 Leopards and 4 Blue. Our one remaining Guppy seems unscathed and absolutely fine! Is it possible he might be responsible for the de-finning and ultimate demise of his three amigos? As you've probably surmised, we are novice fish enthusiasts, having started keeping fish at the end of March. Most of our purchases ( Tetras, Platys and, more recently, our unfortunate Guppies) have been the result of advice given by a Fish Specialist shop in Rhyl from whom we also bought our tank & equipment. We have already decided to get a second tank. Ta muchly, Don & Jenny <Hello Don & Jenny! Guppies can be nippy towards one another. Males are aggressive, especially when kept in small groups without females. Whether to the point of killing each other I cannot say. Never heard of that. Possible though. I have no idea what "leopard" tetras are. Never heard of them. Do you mean Leopard Danios? Small, minnow-like fish with spotted bodies that swim blazingly fast? Danios can be pugnacious, and tend to be fairly high energy animals. Work best in groups of 6 or more; any fewer and they often harass their tankmates, not out of malice really, but simply frustration, and the need to chase things and burn off some energy. Blue Tetras are fairly uncommon and I don't have personal experience, but they're said to be peaceful. Neons are not normally nippy but they have been know to bite Siamese fighting fish, so the possibility of nipping a fancy guppy definitely exists. As for questions of "happiness", there's two kinds of happy. There's what works now, and then there's what works in the long term. Your fish quite probably are happy know because they're young. Fish are often adaptable animals and will thrive in less than perfect conditions. But clown loaches and Silver Dollars get big and live for 10+ years, so long term you need a plan. I'd recommend keeping an eye out over the next 6-12 months for a bigger aquarium. There's nothing more miserable than a big clown loach by itself wedged into a too-small aquarium. Clown loaches are notoriously sensitive, sometimes making suicidal jumps out of aquaria when they feel stressed and other times getting Whitespot very easily. Clown loaches are "allergic" to most standard medications, as I trust your retailer told you, and you must never use things like anti-Whitespot potion in a tank with clown loaches. Hope this helps, Neale>

Silver Dollar Tetras   5/10/07 Hello was looking at your site under Characins, the two silver dollars, Myleus schomburgkii and M. rubripinnis are listed under other sites as reaching 39 cm long. Yours were juveniles then? < Probably close to adult size.> , anyway my question was the teeth. Do they bite your hand if you put it in the aquarium, do they attack other fish, harm them? < They usually attack plants. We use to call them plant piranhas. If they think that your hand is food then they will take a nip. This usually happens when people are trying to feed them by hand. The bites do no damage to the best of my recollection.> I know about the common smaller silver dollar M. hypsauchen do they also have sharp teeth but don't use them? I'm trying to figure out if I can put these larger silver dollars into a big aquarium with Tinfoils, balsa, one Oscar. < Silver dollars make a fine dither fish for med to large community tanks. Just remember that they love to eat plants and need some plant material in their diet.-Chuck>

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