Tubing of Sump return

[maroun.c]

Hi,
I'm planing my sump for a new tank and realized that I might need to have 3 elbows in the tubing of the return. i know that the elbows will affect the flow and maybe the pump so I'm wondering if I should go with 45 degrees elbows adding one elbow then a portion or tubing and then another elbow or just go with a flexible tube?
I'd rather have the PVS tube over hte flexible tubing as the flexible ones might collapse or get punctured or maybe squeezed... so would it be ok with having the 45 degress elbows? I have heard of flexible PVC tubing however it's not available here.
Thanks for any input.

[sjames]

Here is a link to the calculator to figure this out:

http://www.reefcentral.com/calc/hlc2.php