A 65 is a nice size, I started with a 55 then 90,120,180,90,150,65,70 with a few 29 Bio-cubes and a 8 Cubes, Those cubes look nice but they just don't work oh ya I had a real nice 39 Cube it was nice but alas wanted some thing bigger, This 70 I've got now is it no more upgrading or down. I got...