hey thinking of getting a larger tank.
woundering what size would be suitable for maybe 4 O's and a couple of bristle nose catfish.
also methods of filtration what would be a good filter upgrade mine atm is and external canister and does 1500L/h. im thinking i would need something a bit better. and info would be at help thanks!

for long term projection, 125 gal is ideal for two 0scars.
having said that, any additional should have at least 25 gal
per head. catfish is known to be bottom dweller, those their
presence will be covered by good filtration for 175 gal tank.

IMHO...4 O,s and catfish would require 300 uk gals + ...and 2 fx5 filters !!!

from experience having four oscars and a couple of cats i would recommend at least 200 imp gallons and adequate filtration to go with it.

as for filtration i think you should go with a 50 gallon sump and an fluval fx5.


just my opinion