Closed Loop Or Not??? What Is Your Flow Rate's
 

Well I have a dilemma facing me at the moment. I have been thinking of doing a closed loop on my 165 gal 8' tank. BUT I don't think my coral would like a flow rate of 2500 GPH.

Today I am doing a little experiment with my 155. I have a 1100 GPH return and 4 - 1300 GPH power heads but I noticed that a few a my coral were showing signs of not liking that strong flow. So what I have done is shut off 2 of the power head and moved the other 2 to the bottom back of the tank (opposite corner's) facing each other. So now every thing is full open and looking good.

So what I am asking is, anyone that is running a closed loop what is your flow rate? What size of pump are you using? How do you have it plumbed in?

Pictures would be great to see as well. Thanks to all in advance.

You've only got about 40x turnover in your 155 by the sounds of it... which really isn't so strong that nothing can like it. It could be more your coral placement, rather than flow.

2500GPH in your 165 is only going to be 15x turnover + return... which isn't enough for SPS for sure.


I would run 4 holes down the middle of the bottom of the tank, and the intake mid-way up the back wall, or at least high enough that its not sucking sand up.. You may want some ball valves before each return bulkhead so you can adjust the flow in each 1/4 of the tank.

Couple pics of how I plumbed mine.

http://img.photobucket.com/albums/v3...k/75plumb2.jpg

Like I said, run the intake on the back wall, not the floor like me.. ;)
http://img.photobucket.com/albums/v3.../CLreturns.jpg

http://img.photobucket.com/albums/v3...k/75plumb7.jpg

http://img.photobucket.com/albums/v3...k/75plumb1.jpg

In my 330gal I have 2 2500 gal/hour pumps plus a 3600 gal/hour return pump. At this point im still not sure if it is enough. Oh and the 2500's are on om 4ways. You can check my build thread for pics n such

Are you running a 4 way or just teed off the return of the pump?

Edit.....

It was a Snapper Pump.. it was a closed loop, nothing was T'd off the return. And nope, I didn't have a OM4. T'd to 3 bulkheads w/ ball valves to even out the head pressure at each return outlet.

100% closed loop.. power heads suck...

Ok well what i was thinking was drilling in a 1 1/2" bulk head in the middle back, building a 4 port intake (facing up) about 4' long. Then drill in 4 - 1" bulk head returns along the back spaced 1'-2'-2'-2' from leftside of tank wall to the right. Put 1" 90's facing the front so it creates a clockwise flow. Bottom, up the front, towards the back and then down. Was thinking of a 4 way but I don't have the cash because the 155 has not sold yet. I have a return pump that will do 1100 GPH with the length of the return line's I have done.

So long winded but what do you think is it worth it??

I personally wouldn't have a Closed loop again.. My last one was a ton of work, and I still needed to add a powerhead. Plus IMO it is harder to sell a "drilled for closed loop" tank down the road.

The other thing I was thinking was just putting my 5 or 6 1300GPH power heads down near the bottom on the back of the tank facing forward to create the clockwise flow.

I've got a Dart/4way CL on a 145g with about 1000gph return, I'm happy.

For a really well done CL layout, check Dez'z build.

Good thread for what others are pushing here.