filter for a 140 gallon tank... ?

[Hap3niz]

i have nooo idea what kind of filter to get...
it has a black abs overflow box...
measurements are 64x19.5x29


black sand or black gravel at the bottom...
JD's
GT's
Convicts
Plants



ideas...
maintenance info...
lighting...


any info will help!!!!!!
thanks!!!

(oh... if it has a painted black on the back and sides... can i remove the black from the sides??? if so.. how???


thanks!!!!!