55 gal and dont know what to do

55s are too small for Oscars, period. The width is in some cases less than how long the fish can get, jeeze give them some room.

Yeah you can do that Sublime, but just with me I think a 75 would be more suited for them. A 55 would be a minimum though.
 
Check the ph and hardness of your tap water and then research fish that live in that type of water. It will be easier and cheaper. good luck.
 
Sw

You could go SW fairly easy with a Fluval, as long as you dont go reef. I have a 55G FO tank and the hardest part was keeping water in the tank. I suggest if you do want a SW tank, go with the fish first, manage that, and then slowly move up to whatever you want.

I also happen to have 2 other FW 55's, one being a critter tank and one being a Medium Aggressive tank. My critter tank is full of many kinds of shrimp, a few crabs, 2 FW lobsters, and plenty of hiding places. My other 55 is 2 hampala barbs and a 18'' fire eel. There is so much you can do if you do your research.
 
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