Closed loop ?s

[iyachtuxivm]

So on my next tank 225 acrylic I want to do a closed loop. I am tired of seeing power heads and cords in the tank. I really dont know the ins and outs of the closed loop system. I understand the main idea but have questions like-
How do you determine pump size?
How many outlets do I need/can I have?
What size should the inlet be?
Where are good locations for inlet/outlets?
What kind of pump? Should it be pressure rated?
Emergancy back up precautions?
Any and all knowledge, help,comment is welcome and appreciated.
Thanks

[jimsflies]

There is 0 head loss on a CL so the big thing is just decide how much flow you want in the tank and where you want it and that will give you the idea for what pump to use and plumbing sizes to go with :)

Just a slight clarification...there is no elevational head loss. You still get losses from the pipes, elbows and other fittings...normally minor factors in comparison to elevational head loss. Here is a tool (http://www.captivereefs.com/forum/head-loss.html) to help you determine if head loss might be a concern.

I had a closed loop on my 50. It worked out okay. I was always a little nervous with that many holes in the back of a glass tank. You won't have as big of a concern with an acrylic. I doubt I would go back to a closed loop with the variety of awesome, low profile, high flow, energy efficient power heads on the market now.

To answer a couple of your questions, you should have more than one inlet if you can, or at least a tee inside of the tank on the inlet. This will help keep the inlet velocity from getting too high and sucking livestock into the closed loop.

Sizing of piping depends on the flow you want to achieve.

[iyachtuxivm]

Just a slight clarification...there is no elevational head loss. You still get losses from the pipes, elbows and other fittings...normally minor factors in comparison to elevational head loss. Here is a tool (http://www.captivereefs.com/forum/head-loss.html) to help you determine if head loss might be a concern.

I had a closed loop on my 50. It worked out okay. I was always a little nervous with that many holes in the back of a glass tank. You won't have as big of a concern with an acrylic. I doubt I would go back to a closed loop with the variety of awesome, low profile, high flow, energy efficient power heads on the market now.

To answer a couple of your questions, you should have more than one inlet if you can, or at least a tee inside of the tank on the inlet. This will help keep the inlet velocity from getting too high and sucking livestock into the closed loop.

Sizing of piping depends on the flow you want to achieve.

Thanks great info.
Not to sound too dumb but in the head loss calc if I have /want 4 outlets and I choose 4 do I need to up the number of 90s,unions and ball valves to accomodate all the pipes? or does it automatically figure that in?

[Tankster]

Put in an Oceans Motions 4way to alternate flow between outlets Oceans Motions :: View topic - Tankster's 120g w/ 4way (http://www.oceansmotions.com/forum/viewtopic.php?t=1131) I've got an extra for sale.