Author: Brooke Ashley Mullis of “Advanced Aquarists”
Silver dollars are medium to large disk shaped fish closely related to piranha and pacu. The are found throughout South America in slow moving rivers and swamps around thick vegetation.
They are a disk shaped fish reaching sizes of between 5-9 inches across depending on the species. Besides all looking like large silver coins some species also have spots and stripes and red/orange on the body and fins especially on the males.
While there are many diverse species of silver dollar only the two most common species are described here as thier habits and care are similar. (metynnis argenteus (common silver dollar) and metynnis lippincottianus (spotted silver dollars).
In the wild they are mostly vegetarian but are opportunistic so the occasional bug or small fish can be on the menu if it is slow enough to catch.
Silver dollars are a fairly long lived fish with life spans over 10 years with proper care.
Breeding consists of the female scattering up to 2000 eggs in fine leaved plants or in the substrate of still or slow moving areas of the rivers. Females are slightly larger and more their bellies are more rounded than the males. The males are slightly smaller with red on his anal fins.
-In the Aquarium
Silver dollars are fairly commonly seen in store particularly the metynnis argenteus (common silver dollar) and metynnis lippincottianus (spotted silver dollars). And are fairly reasonably priced. They reach a max of 7 inches for the common variety and 5 for the spotted.
Silver dollars are opportunistic feeders but lean more towards the vegetarian diet with occasional snacks of bugs and small fish. so providing them a good tropical or herbivore pellet/flake food as well as a variety of fresh veggies and plants such as zucchini, cucumber, romaine lettuce, spinach, and duckweed and spirulina brine shrimp . They also enjoy dehydrated seaweed and algae wafers. Occasionally giving them krill or chopped up shrimp will help the males orange colors to really pop. Though this should only be fed occasionally as a treat.
Although silver dollars are fairly small fish you need to keep a school of at least 5-8 of them for them to be comfortable as they are a schooling fish. They can do fairly well on their own or with other metynnis species but will show their best color and activity when kept in schools of the same species. Due to the need for a school I wouldn’t suggest keeping them in a tank under 75 gallons.
Silver dollars are fairly timid fish and do best in heavily planted tanks with lots of places to hide. Generally with silver dollars, artificial plants are recommended as they will devour any real ones.
Silver dollars are fairly easy to breed, though you need a large tank. purchase about 6-8 juveniles and allow them to pair off naturally. While the parents will generally not eat thier own eggs the other silver dollars might so after they have paired it is best to separate them.
Provide them with soft slightly acidic water and fine leaved plants to spawn in. The female will scatter the eggs on the plants and tank bottom. The fry hatch in 2-3 days and are free swimming in another 3 days. Feed the fry baby brine shrimp and ground spirulina flakes or specially prepared fry food.
Silver dollars are peaceful and are compatible with anything they cannot fit into their mouths (or can fit the SD into their mouths).
Tank mates can include but are not limited to:
Larger catfish (but not big enough to eat them)
Tin foil barbs
Replies and Comments:
@Reply: Looking for some advice on keeping “moss balls” in my aquarium. I have a bunch of tetras and silver dollars. Does the moss spread?
- I have some that has spread to the top of a piece of driftwood, and I have to say, it is quite nice there. Some also started on my prefilter, and I like that too, but have to keep it a bit under control to maintain a good flow.
- They’re honestly the only plant I can manage to keep right now in my fish tanks lol. They’re so easy to care for and they’re just so unique. Warning, once you get one, you’ll want more.
- Mine fell apart! What can I do to fix this issue?
- I think my algae eater swats it around a little too much. I try to keep it moved out of his way but I think he hunts for it. Lol
- They’re supposed to act like a tiny bio filter…they’re good if your ammonia is high too just keep. Away from cichlids they rip the balls apart.
- They function just like any other plant. They are aesthetically pleasing and absorb some nutrients that would otherwise be absorbed by algae or build up in the tank.
- Our local Petco ( I know not everyones favorite) anyhow they sell singles for $9 in the tanks but if you go to the beta section they put 3 in a container for $9 just something to think about on your hunt.
@Reply: I have a question about silver dollars. Would prefer someone who has kept them to answer. Do spotted silver dollars and common silver dollarsgrow to the same size? Is there any other differences besides the spots? What is their lifespan or how long do they live?
- the only thing I know – we adopted 2 from family. I had abunch of beautiful neons and tetras and danios — but not after the silver dollars came. I let the family take care of the tank – then when they expired — I took it back over. Now it is planted with many beautiful schooling fish. Moral — don’t mix them unless you replace them.
- I’m working on setting up a stock list for one of my tanks and I have three spotted silver dollars but not sure if I would rather have them or common silver dollars. Did they kill your fish? I’ve heard they are peaceful if kept in a small shoal or school.
- Yup — they ate them – or killed them. One day the school was there — then down one and another and another. Maybe b/c there were only 2 sd and they were in a tank alone, Maybe coincidence — but had a pretty decent sized school — and when they were introduced – they were gone. They were about palm size. We did give them a nice burial in the flower pot when they passed over a year later.
Beautiful — but I think my 29 was not big enough for the school and the SD. Even now with 37– I don’t think i would introduce. Keep thinking about angels — but I have heard that SD and angels can go either way — nice or mean. I just got the dominant ones.
I am not sure which ones we had. They were pretty. We just didn’t have means to properly love them like they should have been. Enjoy loving yours — I know it will be awesome. I am sure they are beautiful in a better school.
@Reply: Any of you in to blood parrot cichlids? I have had some for around 7 years and then they just started dying off. They were just fine and then all of a sudden they died. All my other fish are fine and my water is good. The tank is a very well established 125 gallon. I have 2 big canister filters and I have well water. I was just curious about these things. I know some folks have mixed opinions on these fish. Also what tank mates do keep with yours? I have silver dollars and Lear tail upside down catfish and I had a big tinfoil barb. Thanks. P.S. What size aquarium do they need?
- I just lost mine, he was about 7 years.
- Well, their life span is about 5-15 years so yours fit in that span. Also they’re a relatively new breed still so I’m sure that plays into it.
- I have 2 but I’ve only had them about a year, sorry you lost yours frown emoticon I have a gourami, tiger bars, silver dollars and kribs.
@Reply: Anyone keep silver dollars with dempsey fish? any “Electric Blue Jack Dempsey” owners here? I currently have 55 gallon tank. I wonder how many i can stock in this tank? Suggestions? I want at least a pair. Thanks guys.
- Don’t they need at least 75? Are they mean or aggressive at all?
- I’ve wonder the same thing. Some sites says 55 is fine for a couple….some suggest 75 or 100…i am confused.
- I know. It’s hard to figure out the actual needs with so much contradictory info. Maybe start with juvies and upgrade as they need it?
- Yeah, thats why i posted here for suggestions from the pros and experienced bjd keepers. Do you own a pair?
- No (not yet). I was debating between oscars and JDs. Went with an Oscar in my 75 for now and was considering a pair of JD in my 90. From what I was able to ascertain, they would be ok in a 75, but I think would outgrow a 55.
- I have one in a 55 along with a Tiger Oscar and a Silver Dollarand they are fine. Plenty of filtration and regular water changes keep them in fine health. They (Jack and Oscar) will both eat from my hand.
- Yes I have two Fluval C4 on my 55 Cichlid tank good for 70 gallons each and on my Other 55 with the Jack and Oscar I have two Aquaclear 70 made by Fluval.
- I have one in a 55 gal now mine is a slow grower if I wanted I could add at least 10 more and it would be awhile before I had to upgrade them.
@Reply: I’m setting up a 75g, can silver dollars go with angels, barbs and tetras?
- The only problem I would see there is the Angels getting out competed for food as dollars are greedy fish and can be quite boisterous at feeding time.Plus you wouldn’t get many dollars in a 75g as they get pretty big when fully grown.
- i wouldn’t recommend tiger barbs with them at all, i had a bad experience with some barbs i had, they killed 2 of my silver dollars last year frown emoticon .. so i re homed all of them. but i keep a black marble angel fish, and he is fine on his own… and a bunch of different tetras… they all get along fine, and have plenty of territory space!
- I have tiger barbs with my silver dollars and they all get along fine but maybe I got lucky with mine.
- same here, i made a 29 gallon barb tank with mine after they terrorized my bala shart and Silver dollars.
- i’ve kept them and loved them but I could never keep plants and I think i prefer the plants to the fish.
- i’d love to keep real plants, but as you know it can’t be done! sometimes i notice them, chewing at the fake plants lol.. they are so greedy, and i give them spinich and lettuce daily!
- there is a pellet food that is made for them but I can’t remember what it’s called.
- i do give them tetra algae wafers like emoticon they love those, they flip them around as they eat them.
@Reply: Who is keeping silvers? I love these fish!
- I have three the size of my fist, and three the size of dimes that are growing quickly.
- All of mine are between 3 and 4 inches long now.
- I have had them before, and I am getting some as soon as I get my other tank set up.
- Yess and i love them…they swin and play together.
- We have 1 male 3 femal been trying to spawn for years.
- mine have laid eggs twice before, but all of them were eaten, and i wasn’t intereted in breeding them anyway! fresh food.
- Found a good deal on a 260 gallon tank, stand and cover….might be time to upgrade the 125!
- Going to move my Oscars and large Plecos from the 125gallon to the 260…then maybe another Oscar or something else…my wife likes the arowanas…. But that would free up the 125 to consolidate my other tanks into…so that will turn into a big community tank…Cory cats, black neon tetras, khuli loaches, albino bn Plecos, and silver dollars…
- That’ll be awesome. In into predators myself, I have bichirs, eels, large American cichlids and puffers.
- I kinda inherited 3 Oscars…they’re cool fish…such personalities…they just need a ton of room! And I am probably more excited about being able to use the 125 for the community tank than I am the 260 for the Oscars!
@Reply: Several times a week someone asks about tank mates for a Betta.
No one ever asked about tank mates for an Oscar.
My next project is a 120 gallon Oscar tank. It has a built in overflow, I will also be using a canister filter.
I would like some kind of catfish. Problem is I don’t think any catfish grow as fast as an Oscar.
A lot of fish won’t mess with a catfish no matter the size.
- I had a huge pleco with my two oscars until they started to spawn and tried to kill it. Some people have good luck with silver dollars and oscars.
- Silver dollars require schools?
- Yeah any were from 12-18in is the normal max size for bullhead. They grow decently fast. If you feed them high protein they grow very fast and get all plump and lazy. If there hungry they get very active. I have seen mine eat rosy reds ect.
- So an Oscar and a Bullhead in a 120 would be okay. Of course I would do much more research.
- Yes you will be ok. You can order bullhead from a few sites online or you could just go to some local fishing spots and catch one by rod and line.
- I am thinking about a blacked out tank. Painted black on the back and sides. Some black rocks for a catfish to hide under. Some dark driftwood and a bright light.
- A lima shovelnose. They grow just as fast. They don’t get as big as the tiger shovelnose. Most other cats are gonna outgrow most tanks.
- Look into featherfin. Oscars arent overly aggressive if given plenty of space. So the cat would likely just need to stay big enough to not get eaten.
- Redtail catfish, gulper cat, pictus cat, make sure the Oscar is bigger then a gulper cats mouth. I have a arowanna and a pleco with my Oscar might get a ray as well.
- Oh well yea. I just skimmed through it. I have no clue then I have a pictus cat but it’s still small. Have had it for a month and it’s only grown a little.
- A lima is a good choice. Or synodontis catfish species. With gulper cats youd really want a full grown Oscar before you introduce a gulper. Gulper cats can eat prey the same size as them. They are literally tanks.
- Gulpers frighten me. I don’t want to have to wrestle my arm out of its mouth while doing tank maintenance.