do a severum tank as yakuza said i have a severum tank 75 gallon and it looks good, 3 oscars is gonna get bad, i guess you could go with that, i personally dont like oscars but it doesnt matter but prolly shouldnt get more than 4 or 5 i just got a 125 and my stock list is 2 rb snook maybe a bn pleco and a severum, make good decisions, research alot before you buy, 3 o's is deffinitely not a great idea but who knows it might work out for ya