Im new to here and i was just wondering if its best to just have one flounder or by them in twos. Never had them before and think they are interesting to watch.
I have three of them together for about 1 1/2 years and they are all doing great and they all look like they get plenty of food because they all have at least doubled in size.
If you have a large tank for flounders, you could try hooking up with California members to get a couple of starry flounders. These riverine (read: light brackish) flounders easily grow to the 1 foot mark and have more interesting color patterns than other species (IMO).
Starry flounders are great fish and very tasty but do best in unheated brackish to salt tanks and get quite large (up to 36" with 24-30" being fairly common), here is a pic from http://www.afsc.noaa.gov/race/media/photo_gallery/fish_files/Starry_flounder.htm
If you want something from a little closer to home that maxes out around 8" you could get a hogchoker (trinectes maculates)or so, they tolerate freshwater pretty well or full salt and anywhere between, and are found along most of the USA east coast up to 200 miles up river. They tolerate a pretty wide temp. range but again do best in unheated tanks. Flounders and soles eat small fish and inverts, and can be adapted to pellets sometimes. They do tend to nip fins of fist that swim over them but tolerate being alone or in groups. they are not territorial but sort of ignore each other unless breeding or differentin size enough for one to get eaten. Here is a pic by Tom McHugh