Thanks for the tip on the durso Sanj, never heard of those before. Looks potentially quite useful.
dw1305 I've got a great pump already thankfully (in fact quite a few…
Picked them up over the years.
I'm putting the sump in my cellar and the aquarium's in the ground floor living room so the pump has to be pretty powerful to pump that much head. The one I'm using is this at the moment:
Handy link Garuf, it'll take me a while to get through that! I completely forgot to check the Aus forums, they're always useful (guess they have to improvise more Down Under because stuff made abroad is so expensive!)
Bobtastic I believe the flow gets distributed across the entire surface area of each compartment rather than through the narrow confines of a closed loop system.
Here's my final design. Implemented a few of your suggestions dw1305:
I've made the end section to the pump very large to accommodate heaters lying flat (eg. the Jager 200W heater is 18", the 300W is 20") as well as airstones, and any additional equipment which I might want to throw in there. Seems a huge waste of space though which I could use for media...although doing a quick calculation shows the first section will give me 29 litres of media volume and the remaining two 22 litres each.
To put it in perspective an Eheim 2080 has 13.5 litres of total media volume.
Think it's good enough to send off to get built. I only need to add two holes to the drawing which need to be drilled for the outlet to the external pump. Any recommendations for good aquarium/sump manufacturers?