(not from the net!)
I must say also that the Silver Dollar is a fantastic fish, having had them time and again. They grow as quick as anything, looking big, bright and shiny with a personality to match. I have had fish all my life and every time I set another tank up or start new stock it goes without saying that I include dollars. I always find that they mix well with all types of fish. I have a good assortment of catfish that they get along fine with. As for feeding, they do love all aquatic plant life, the only thing they tend to spare is the egeria densa (elodea densa). Try a slice of cucumber weighted down with plant weight. The plecostomus like this treat too. Also try koi pond sticks and balls. They play underwater catch with them, letting them go and catching them as they float up, then they eat them in seconds.
I have 3 Silver Dollars and after reading the above comments I think they are related to some of your fish! They started out small, about 5 cm and have grown in 6 months to be about 10 cm. I have an 80 litre tank which the dollars share with 4 fancy and spoilt Goldfish. The Dollars are quite nippy at the moment and have nibbled the fins of the Goldies! Now it appears that one of the Goldies (BJ) has become part of the Dollar clan and they school together. The Dollars can be aggressive around feeding time and this causes me some angst as I am very fond of my fancies :-) All in all they get along well but I wouldn't put them in with any precious or really slow fish. I am learning more and more about fish every day and they are a wonderful alternative to watch rather than the TV.
These are GREAT fish. I've had two for two years now in pH 8 water. They adapted fine so far. They are hardy fish - never caught other fishes' diseases, and recovered well after hitting the floor once. They are flashy as polished sterling silver and really active. I love their behavior - flashing at one another, playfully chasing, and playing football with their food. Mine love spirulina discs, celery tops, lettuce, spinach, zuchinni, flakes, even betta food. They really put the piranha action on their vegetables, gnawing them down to nothing in minutes. They are docile. Mine don't even notice the 3 cm cherry barbs in their face. They are easily frightened by movement outside the tank. Mine hide in driftwood for refuge when there's too much activity in the room. However, they need LOTS of space. I will sadly have to give mine up soon as I only have a 110 L.
I have 8 Silver Dollars (4 red fin, 4 spotted) in a 280 L tank. I agree with some of the other comments about these fish being timid. They are not agressive toward my other fish, but at feeding time they go into a frenzy, even taking food out of the mouths of other fish. Sometimes I worry that my other fish are not getting enough to eat. I had them in a 73 L tank before moving them to the larger one and they always seemed to be stressed, any movement outside the tank scared them. But as soon as I put them in the larger tank they calmed right down and will now come to the front of the tank and watch anyone sitting there. All I ever feed them is flake food and algae tablets meant for the Pleco. Every time I tried to give them lettuce they won't go near it, they seem to be scared of it. One food all the fish in my tank love is freeze dried (freezer burnt) hamburger. I put a few slivers of that in there and the fish go crazy. The catfish gourge themselves on it. I really love my Silver Dollars but it is hard to find any good info on them. This is the best website I have found so far just from the comments other people have made about their fish. My only advice is the bigger the tank the better for Silver Dallars.
I have 2 silver dollars. Currently, I feed them frozen bloodworms, lightly boiled and then cooled peas, small chunks of prawns, beef heart, worms, lettuce, algae discs, celery tops, chiclid pellets and sticks, brine shrimp cubes, tubifex cubes and discus granules. They need LOTS of space. I keep them with 2 cory cats and 1 pleco. I decorated their tank with a formation of rocks and plactic plants (they eat all the live ones). Sometimes, I would bury tubifex worms for the corys to find. And when the corys found the worms, the silver dollars would share the meal (in fact, the corys would not mind a bit). I just love my fish!
I have had 4 silver dollars for 2.5 years and first housed them in a 125 liter tank, I later moved them into a 570 liter tank. The two smaller ones (12 cm) had black marks, while the large two (14 cm) had bright red hook marks on their lower fins. After 1.5 years they began regular spawning - the smaller ones would shimmy against the larger until the larger (females) dropped eggs. They repeated this every 30 minutes or so for about a day, dropping 20-30 eggs. I was unable to collect any eggs before their cichlid tank mates found them, and connected the shimmies with food. Now when the silver dollars spawn the whole tank takes notice.
I have had 2 Silver Dollars for about 2 years now they are in a tank with 3 green terrors, 1 red tiger oscar, 2 red parrot fish, 1 plec and an XL featherback catfish. They all get on great. I really think you can put the dollars in with anything apart from maybe a Red Devil, as they get on with all fish I have tried in the past, nothing can catch them. They have been chased by the oscar and green terrors, but they can't catch them so they have decided to give up. They are great fish that I would recommend to anyone with a decent size tank (at least a 90 cm tank). They love planted tanks so they can hide, if you only have gravel and a rock in the tank you won't get the full benefit of the fish as they are a shy fish. Put plenty of plants in there and bog wood, and you will see their great colours, and maybe they will feed from your hands like mine do.
These pages have enough comments to give the reader a basic idea on the topic. Further comments are still very welcome (through the site's contact form) as long as they provide new and/or advanced information not yet discussed in the existing ones.