New to "Reef Tanks"

[marksm33]

Hello, All,

I'm a freshwater enthusiast and I've decided to give a Refugium a try. I purchased a 125 "reef tank" with two predrilled holes at the bottom of a weir in the tank. The tank came with a Durso pipe. It also came with another PVC pipe with a thinner diameter and flow directors that fit on top. I have two basic questions which will highlight my ignorance, I'm sure:
1) Why are the two pipes different diameters? Is that to give you better control over the flow rate on the return from the sump pump?
2) Am I completely missing it? Is the second smaller diameter PVC an emergency pipe for the weir in case the Durso gets clogged?

Any help would be appreciated and thanks!

Mark

 

[kfisc]

Hello and welcome!

The larger pipe is the drain; the smaller is the return from the sump. They balance the flow rate so that, long story very short, your sump won't run over and you can maintain the appropriate "oomph" to the strength of the siphon with the bigger pipe.

 

[mtnbike101]

Welcome to ReefCentral!

Ideally, you would have (at least) two drains going to your sump. As you mentioned, one would be for emergency, but it also will cut down on noise if the primary drain is tuned correctly via main valve.

That said, the second hole may be your only return option. Do you see any other holes for the main return?

 

[marksm33]

No other returns for the main return. Does this sound accurate:

I'm assuming I will adjust the flow from the pump to tune the tank and have the output from the pump match the drain from the Durso; I'll have to calculate the amount of water that exists above the drain line in the weir in the DT and make sure I have enough room in my sump to accommodate that if the pump fails. In return, I'll have to calculate how much water is in the return chamber of my sump and make sure that there is enough room in my DT to accommodate it if my drain pipe becomes clogged. My sump pump Jabao DCP 5000 has an auto-shutoff if it hits the air. Does that sound right?

I'm using this as a guideline:

Overflow Boxes and Drain Styles - Durso, Herbie, and Bean Animal

Decide which of the three most common types of drains and overflow boxes is right for you and your tank.

www.bulkreefsupply.com

 

[kfisc]

Looks like a good guide. It's worrisome at first to ponder all that water flowing back and forth, but in my experience it's fairly rare for a well-installed, standardized drain/return system (not DIY) to clog or fail. You definitely have to make allotments for spillage relative to the size of your sump. This can be accomplished by shutting off the pumps and watching the drainage.

 

[mtnbike101]

Once you establish safe water levels, I'd suggest using painters tape, etc. to mark those lines whereby you know where your top off level should be at any point.

 

[Justint05]

Hello, for the first,I think the two pipes of varying sizes serve distinct functions. The Durso pipe is used as the overflow system's main drain pipe, whose greater diameter allows in managing a higher flow rate while also reducing noise created by water flowing into the sump. The flow rate can be adjusted by adjusting the height of the standpipe in the Durso pipe.
And for the second question,yes, you are half right.The smaller diameter PVC pipe is used as an emergency or backup line. This gives an alternate way for water to flow in the event that the Durso pipe becomes clogged or stopped for whatever reason.

 

[wvned]

I would like to kill a myth here.

YOU DO NOT NEED TO BALLANCE THE FLOW BETWEEN YOUR RETURN AND YOUR DRAIN.
Many of us take a shower every day. Do you turn the shower on exactly enough so that the water goes down the drain and doesn't overflow the tub.
Well gee, no we don't. We just expect the drain to take all the water from the shower.
It is the same with a fish tank. An overflow system should drain away all the water the return pump puts in the tank just like a drain in a bathtub.
A better way to think of it is there is some maximum pump size you can use with a particular overflow system.

A return pipe is smaller because the water in it is flowing from pressure from a pump while the drain is simply letting water fall from gravity.
The closer you run an overflow to it's maximum capacity the noisier it will be.

When you buy a tank with a supplied weir and durso standpipe it tells you somewhere what flow it can handle.
For a Marineland tank for example.
The Corner-FloTM overflow and plumbing are rated for 700gph and this is not affected by the fact that the drain necks down to 1” as it enters into the bulkhead. Higher flow rates can be achieved, but 700gph has been established as the optimal flow rate.

So don't go putting a pump twice that big on the tank and expect it to work.