you know that the likelihood of a bigger tank being purchased is unlikely:D
its usually best to purchase a big one at the start. Reason.
When you have fish, you keep buying fish stuff:D so you waste more money, shall i say SPEND more money, waste is such a nasty word
but i agree, oscars can get big, but if they grow up together, well fed, COULD be ok.
i had an oscar, friendly as hell!
put a jardinii in there..... it wouldnt work, but would be entertaining for a few minutes