3/4bulkhead plumbing question

[1628mna]

i bought a mag9.5 for more flow . in the directions for the mag pump it says that you new to plumb your return with a 1 1/2 return pipe. i have a 90g megaflow tank with a return hole that at the biggest hole it will take is a 3/4 in bulkhead. somebody on here suggested that i use a 1 1/4 pipe from the pump upto the bulkead then thru the bulkead continue with the 1 1/4 pipe. has anyone ever did this or knew anyone that did this? does anyone have any other ideas to solve this problem other than cutting a hole in the back of my full tank or going over the top and thru the hood. please help comments and questions or answers greatly appreciated!!!

[reef / aholic]

The mag9.5 has 3/4" outlet, just continue with 3/4" all the way thought the bulkhead to your 3/4"return.

The only thing do not restrict the inlet of a pump by using a plumbing fitting with a smaller diameter than the pump inlet. This will cause cavitation as well as a great deal of noise

[Toddrtrex]

Mags are suppose to be run with wider pipes, so you should stick with your plan.

While I am using a different pump ( Velocity T2 ) I am doing pretty much thing. Using 1 1/4 pipe all the way to the bulk head ( which is 3/4 ) then back to 1 1/4. It will work fine, with with the smaller bulk head.

[1628mna]

thanx todd will do

[sjm817]

Yup. 3 options (if you want to get a lot of flow:

1) Run bigger plumbing before and after the bulkhead
2) Run bigger plumbing over the back and bypass the bulkhead
3) Use a better pump that doesn't need huge plumbing to get good flow.

[reef / aholic]

Originally posted by Toddrtrex
Mags are suppose to be run with wider pipes, so you should stick with your plan.

Generally, most pumps have an outlet connection smaller than its inlet connection; this is so the pump can use velocity pressure relationships to its advantage. When plumbing your return, it is advised that you step up the piping to the same size as the inlet piping, or one size larger. Also when sizing your plumbing, you need to consider the friction loss in a (pvc pipe table and pvc fittings table). You want to ensure that you don't buy fittings, valves and piping larger than what you need. So I corrected myself from my earlier post!!!