freshwater flounder

[flushingfish]

Anyone have any ideas what these things eat. I have 2 in my 20G planted community. I don't think I've ever seen them eat. When I read up on them and spoke to my LFS i got the impression that they are carnivores or at least omnivores. I feed a mixture of tropical flake, bloodworms and sinking pellets. They were both very active in the tank and now are slowing down greatly, one barely moves at all anymore. Is there something else I should be feeding to make sure they eat? Maybe spirilina tabs? All the other fish eat like there's no tomorrow.

[hc8719]

are the bloodworms frozen of freeze dried, alot of picky fish will only eat frozen.

fw flounder are also brackish fish i believe, and may not be as forgiving to a fw enviroment like mollies, or some gobies

[flushingfish]

I was just doing some more reading and just found an article that says they prefer live food such as brine shrimp or frozen bloodworm. I have been using freeze dried. Will be stopping at the LFS for some frozen tonight.

[hc8719]

yeah freeze dried is good for common tank fish, but BGKs, fw stingrays, elephant noses, and apparently flounder, refuse to eat freeze dried most times

i usually pay around $3 for 4 oz of sally's bloodworms

[andywg]

Flounders are pretty heavily nocturnal feeders and do not do well at competing with other bottom feeders for food (such as plecs, corys or other catfish). There are some that live their whole lives in FW, but I seem to recall the most common one seen in American lfs is the Hogchoker Sole which is a low end brackish fish.

Best thing to do to try and see them feeding is to put some frozen or live bloodworm in once all the lights (tank and room) are out and shine a torch with a red light into the the tank to view (most fish have far greater sensitivety to blue light than we do, but are comparatively "bad" at seeing the red end of the visible spectrum.

Most soles and flounders are known to get somewhat predatory as they grow, though the size of the mouth is not massive compared to the size of the body so it is not like keeping a gulper catfish.

[Blazeherd2306]

First and foremost, flounders are brackish water fish. A brackish water environment is a must if you want to keep them healthy. Their lifespans will be reduced in freshwater. Unless you know for sure the hogchoker you received came from a freshwater source (somewhat rare with brackish water fish, floods and drought cause some to become isolated in freshwater, where they can learn to adapt....the same will not easily happen in an aquarium).

I think the type you are talking about (Hogchokers) get about 6-8" long, so they need a large sand bed to roam around on. Your 20 gal might be okay for now, but they will need a bigger tank eventually (I'd say maybe 55 gal at least). Their natural pray are brackish water shrimp and small live fish. I don't know how well they adapt to "non-alive" food. Certainly blood worms, brine shrimp, ghost shrimp, and other worms would be good food for them (preferably alive).

HTH and Good Luck!

[flushingfish]

They seem to take really well to the frozen bloodworm. So I think that's one problem solved.

[tropicfishman]

doesn't thatbecome a rather large fish? lol

[Blazeherd2306]

They only get a max size of 8" and most are reef-dwellers. They sometimes go upstream into freshwater or estuarine waters.

[andywg]

Originally Posted by Blazeherd2306

First and foremost, flounders are brackish water fish. A brackish water environment is a must if you want to keep them healthy. Their lifespans will be reduced in freshwater. Unless you know for sure the hogchoker you received came from a freshwater source (somewhat rare with brackish water fish, floods and drought cause some to become isolated in freshwater, where they can learn to adapt....the same will not easily happen in an aquarium).

They sometimes go upstream into freshwater or estuarine waters

If you look at this information by Neale Monks (an author and editor on brackish aquaria and fish) you will find there are a number of completely freshwater species of sole, including:

Some of Cynoglossus spp
Brachirus harmandi
Brachirus pan
Synaptura salinarum

However, identifying to a species level is not easy, and even the completely freshwater fish can easily tolerate a low end brackish level, so (just as with any goby you are unsure of) I would recommend keeping at a low end brackish (SG 1.003-1.005) until you can be sure of an identification.