HUGE. I'd say for 3 Oscars with no tankmates 150ukgal as an absolute minimum and you will need about 6-10x turnover for filtration.
I'm going to have 2 in 150 UK gal (6x2x2) - with carefully chosen tankmates and massive filtration.
I think 3 is asking for trouble though, even in a big tank, the smallest/weakest is highly likely to get bullied.
Even 2 together will not always work and even O's that grow up together can start fighting as they approach maturity (anything from 8" onwards)
HUGE. I'd say for 3 Oscars with no tankmates 150ukgal as an absolute minimum and you will need about 6-10x turnover for filtration.
I'm going to have 2 in 150 UK gal (6x2x2) - with carefully chosen tankmates and massive filtration.
I think 3 is asking for trouble though, even in a big tank, the smallest/weakest is highly likely to get bullied.
Even 2 together will not always work and even O's that grow up together can start fighting as they approach maturity (anything from 8" onwards)