Return pump. Do I need new pipes?

So this might be a dumb questions but I am looking at getting a new return pump Ocean Runner 3500 900GPH 4 foot head at 792GPH for my 90G which would give me just under 9x turn over to much? Also I am using a mag 7 right now with vinyl tubing can I still use the tubing and just change the Ocean Runner outlet if it does not fit or does everything have to be a big enough ID? I have 1/2'' ID bulkhead right now will this still work?

 

Return flow should be 10 times the sump volume. You might be able to change the outlet or make a reducer to fit your current return line.

 

The 3500 works best with 3/4" or 1" return lines. 1/2" will restrict it a lot and cut your flow drastically. A general rule of thumb for any centrifugal aquarium pump is to increase the inside diameter of the plumbing one size from what it comes with to reduce head loss or back pressure. Mag even puts that in their literature somewhere.

You might try increasing the plumbing size before buying the new pump, you would be surprised how much flow you pick up with your existing pump. Go 3/4" all the way and the Mag will come alive. Personally I hate Mag pumps and the OR is a much better choice though. I use a OR3500 for my return on my 100G and its been bulletproof for 7 years now.

 

The problem is my bulkhead I think might have a reducer on it to 1/2'' I can take that off but can not go bigger then 3/4'' think the OR is still worth it over the mag? Disclude your bias I would like to do a 10x over turn but what desertrat said makes me believe anything more then 900gph will be pointless cause of my plumbing.