Decided on going for an island setup with a centre tower overflow which i can aquascape rock around, drill a hole straight through the bottom leading down into the sump. From what ive read centre overflows work well. And it will conceal well id just have to cut it to the exact height i want the water level. Im going to have to invest in a bigger skimmer and some other equipment for the increase of volume... never had a tank bigger than 100L.
Looking foward to building this upgrade. Thanks for all the help. Will share pics when its done