Emergency Overflow

[cba191]

My tank isn.t drilled for an emergency overflow. Would using a water sensor in the overflow for an emergency shutoff be adequate?

 

[JTP424]

You might want the sensor in the tank itself. That way you can confirm the water height in there rather than the HOB box?
I may be confused though... are you using a drilled tank or a HOB style?

 

[cba191]

Its a drilled tank.

Ps. There are only 2 holes. The reflection makes it look like 3.

 

[JTP424]

Gotcha! Yea a sensor would work for you I think.
Check out Autotopoff.com he makes custom ones, price is good too.

 

[exnisstech]

Not a sleek look but I would be tempted to run the large hole as a main drain and the smaller as an E drain and run the return over the back.

 

[cba191]

Not a sleek look but I would be tempted to run the large hole as a main drain and the smaller as an E drain and run the return over the back.

I'm tempted to do that and have dual returns. One on either side of the overflow.

 

[cba191]

Also, when running 2 return pumps in a 150g, would 2 2000gpm pumps be better so you don't have to run them hard?

 

[BryanM]

Also, when running 2 return pumps in a 150g, would 2 2000gpm pumps be better so you don't have to run them hard?

I definitely don't like running pumps over 75%, in my experience they start to get noisy.

2 2k pumps sounds more than adequate to me.

 

[JTP424]

I'm excited for the build thread on this one :)

 

[mook1178]

Not a sleek look but I would be tempted to run the large hole as a main drain and the smaller as an E drain and run the return over the back.

This is what I did with my 75 gallon. It also allows the return pump to use a straight connection to the top. No elbows or turns that slow the flow

 

[UncommonSense]

I'm tempted to do that and have dual returns. One on either side of the overflow.

Best practice is trying to have your emergency drain >= primary drain diameter… otherwise there’s a real chance the emergency drain cannot keep up in the event of a full primary drain clog! (A snail crawling into the standpipe, for example!)

Also, when running 2 return pumps in a 150g, would 2 2000gpm pumps be better so you don't have to run them hard?

3/4” plumbing maxes out around 650-750GPH in a full siphon drain application, 1” plumbing maxes out at around 1,000-1,200GPH in a full siphon drain application!

Keep this in mind, especially with dual pumps! You’ll likely end up being capable of pumping more water into the display than the drain can keep up with if both pumps are at 100%!

(Best-bet here would be looking at each potential pump’s flow curve, and finding a pair that can pump 300-500GPH [observed] at your system’s operating well height (likely around 3.5-4.5ft head)

 

[nick.j.marchetti]

Not a sleek look but I would be tempted to run the large hole as a main drain and the smaller as an E drain and run the return over the back.

New to reefing. I just filled my 180 and as I was doing research on how to silence the overflow, I realized my tank doesn’t have an emergency overflow either. I think I will replumb it with this advice, running the return over the back. Great idea!

 

[UncommonSense]

New to reefing. I just filled my 180 and as I was doing research on how to silence the overflow, I realized my tank doesn’t have an emergency overflow either. I think I will replumb it with this advice, running the return over the back. Great idea!

It’s important to note that your emergency drain(s) should ideally be >= primary drain diameter!

This said, I’d run the 3/4” holes as your primary drains, and the 1.25” holes as your emergency drains!

This is how I plumbed a pair of dual overflow 180G tanks at my LFS, and it’s been working great at around 800-1,000GPH returned!