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JimON
06/02/2017, 08:58 AM
Hi all. I have a 90 gallon with a central overflow built in to the tank. It is drilled on the bottom inside the overflow set for a 1-1/2" sch 40 drain bulkhead, and a 3/4" sch 80 return bulkhead. How does all this go together, and how should it be plumbed? I did a search for overflow diagrams, but nothing seemed to hit exactly what I have. How high should the overflow pipe come up in the box? Where should return be placed, and what additional water movement should I supply inside the tank? I have ordered a CLF-1 sump and seperate refugium, and an ato reservoir from Lifereef if that matters. Thanks for any replies!

nereefpat
06/02/2017, 10:03 AM
You have 2 options:

1. A simple standpipe design, using the 1.5" pipe as a drain and the 3/4" as a return. You can use a durso system on the drain to help with any noise.

2. A Herbie-type syphon system, using the 3/4" pipe as a full syphon and the 1.5" pipe as an emergency drain. You would then half to run the return piping separately over the back of the tank.

What specific pump are you using as a return pump, or what are your goals for flow through the sump?

Most shoot for about 5x turnover of display tank volume through the sump. Most flow in the tank will come from powerheads/wavemakers in the display tank.

JimON
06/02/2017, 11:15 AM
Thanks, nereefpat.

Sounds like option 1 for me, with the durso. Seems like that would eliminate most of the noise. This is the first tank I will have had with a sump, and as I understand it, the main tank stays the same level always with the evaporation being visible in the sump. As such, where in relation to the elevation of overflow notches do I place the inlet to durso, or is the horizontal that passes to the standpipe the critical piece? Is it possible to determine that prior to having things filled and ready to run?

Going to be running a mag 12, and feeding some of that to the fuge. Should be plenty for the return, yes?

Thanks again for the help!

JimON
06/02/2017, 11:35 AM
Answered my own question about the elevation with a little reading on the Durso site. Tell em how tall the tank is and they make it to fit sounds good!:reading:

nereefpat
06/02/2017, 12:26 PM
You may have to play around with the elevation a bit. The durso pipes I've seen are somewhat adjustable. Good you are reading about it.

A mag 12 (1200gph) is plenty, if not overkill. I would make sure to put a ball valve on the pressure side of the pump so you can throttle it back if needed. Or buy a pump (mag 9.5 maybe?) that moves a little less water. Dursos work just fine; they just don't let a ton of water through without making some noise. Too much flow=noise.

JimON
06/02/2017, 01:29 PM
When I ordered from Lifereef, Jeff said that the mag 9 or 9.5, (don't remember exactly), was the standard pump that came with the system. Since I was also going to run a fuge on it he said that I should up it to a 12 to give plenty to that side of it. He has built a ton of these, and am guessing he has it down pretty good. Excellent advice on the valve, and yes, I will be placing inline valves wherever it seems prudent. Controlling flow with an AC pump, gotta have it.

I will keep reading, it appears that Durso also has a pretty good handle on their drain, too. I like the intake they sell for it, makes sense to have an elongated strainer. Never know what could end up in there. Thanks again for the tips!

If anybody has comments on the Durso drain, please speak up!

Lsufan
06/02/2017, 08:17 PM
If your not in a big hurry to get setup I would do some research on the differences between a durso & syphon drain. I wouldn't want to rush to setup then realize that u can't get it as quiet as u like with the flow u want.

I know I wouldn't setup a tank with anything but a syphon. No matter how quiet u are able to get a durso it still won't be as silent as a syphon.

I would think about going with option # 2 . That's how I would set it up. U may want to check the hole size in the tank but I bet u could actually fit a 1" schedule 40 bulkhead in the hole that is drilled for the 3/4" schedule 80. A 1" sch 40 bulkhead is about 1.5" but u are supposed to drill a 1.75" hole. I bet the hole that u have isn't to much smaller then 1.75" if it is for a sch 80 bulkhead.

I would go this route if possible, that way u can run a herbie with a 1" syphon & 1.5" emergency. It would be able to handle more flow & be silent.

JimON
06/03/2017, 09:03 AM
Hi LSUfan. Yes, you are correct on size of hole, it is drilled 1-3/4". Large hole is at 2-1/2". How much more flow would a siphon provide over a Durso?

Lsufan
06/03/2017, 05:44 PM
It will depend on a bunch of things but a 1" syphon can flow between 1,500 & 2,000 gph. A 1.5" durso can probably handle a max of 750 to 900 gph. I didn't look it up so these numbers are going from my memory, so they may be off a little. They should be pretty close though.

Both will be able to handle the flow that u need for a 90 gallon, the biggest difference will be the noise & reliability. The more flow u put through a durso the louder it will be. A syphon will be silent regardless. A syphon once u get it tuned in will probably be more consistent also.

Durso's are a thing of the past, unless u have a really low flow system. A syphon is just a better setup for multiple reasons.

If u decide to run a herbie, I would definitely get a 1" sch 40 bulkhead & use it as your syphon. It will be able to handle any flow u throw at it & remain silent. The 1.5" will be the emergency incase your syphon gets clogged. U always want to use the smaller of the bulkheads for the syphon because if it gets clogged then u know for sure that the emergency can handle all of the flow. If u use the larger bulkhead for the syphon & the smaller for the emergency, if the syphon gets clogged the smaller emergency may not be able to handle all of the flow & u may have a flood.

I would definitely get a 1" bulkhead & use that as the syphon instead of using 3/4".

JimON
06/04/2017, 01:29 PM
Thanks for the info, LSU. I appreciate it.:beer:

So with the return coming back to the tank, just up and over the back far enough down to be under the teeth of the overflow? I did like the thought of having it all contained in the tank, but you have me thinking...

Bruce51
06/04/2017, 05:12 PM
you could always drill the back of the tank for the return. I drilled my 40 breeder after watching a ton of youtube videos. wasn't that hard to do

Lsufan
06/04/2017, 06:15 PM
Yes, u would want it just under the water surface to where it isn't splashing. Remember that the tank will drain down until the end of the return isn't submerged or until it sucks enough air. So u don't want to have your return 6" below the surface or u will drain 6" of water from the tank every time u turn the return pump off. That is one good thing about a over the back return, u can set it up to where u get very little backflow when u turn the return off.

If u go with a herbie u only really have 2 options on the return. U can go over the back or drill a hole in the tank for the return. I have the returns drilled on both of my setups but some of the nicest & sleekest looking tanks out there have over the back returns. I would put two 90's back to back to make a U shape & let that hang on the back of the tank. I think it would barely be noticeable & if u have a canopy then it really doesn't matter anyway

JimON
06/05/2017, 08:02 AM
Thanks, LSU. As I think about it, you're right, canopy will hide any pipes and I can drop it over the back inside the overflow, then drill the acrylic as I had planned with the Durso. Won't look any different! I need to make a drawing of this and get it posted to make sure I am thinking correctly....

Hi Bruce. I am not up for drilling glass, yes I could probably pull it off, but better safe than sorry!

thegrun
06/05/2017, 09:08 AM
Personally if you want a very quiet tank I would use both holes as drains with the 3/4" line as the primary full siphon and go over the top with your return(s).

JimON
06/05/2017, 02:47 PM
I am thinking that is precisely what I am going to do... Thanks!