If the tank is large enough. For rearing young Oscars a 50 gallon tank is about right for 5 fish.
Yes can very well. Fish will only grow to the size of the tank so that means the Oscar will probably only get about 6 inches tops. And i would eventually upgrade to a 30 gal tank withing the next 6 months.
It depends on what size you have. You can have upto 1inch of fish for each U.S. gallon.
Jack Dempsey or Tiger Oscar
Any.
betta fish like at least a 1 gallon tank (nothing smaller) > They can live in a community tank but with no other bettas.
NO! Turtles are reptiles and should be kept in a vivarium never in an aquarium with fish. Reptiles and amphibians will foul the water and the fish will not survive.
length and width for a 55 gallon fish tank
If you do the right thing by your fish it should not be dying. The basic rules for keeping fish are :- 1 inch of fish needs a minimum of 1 gallon of water (Oscars need much more). :- every tank needs a permanently running cycled filter. :- every tank needs to have at least 50% of its water changed every week.. Oscars need a temperature of above 75F and below 85F. One Oscar needs a properly set up 20 gallon tank. 2 Oscars can get by in a 30 gallon tank.
probably a 50 gallon tank would be best.
The only fish you can keep in a 5 gallon tank is one betta (Siamese fighting fish) on it's own as that is a very small tank.
Neons