New Tank Situation.Help Please

[JMorris271]

Hi Guys
The 120gal Deep Blue dual overflow tank I ordered came this morning and already I have a question.
I will be putting in a Herbie system and was thinking that the emergency drain would be 1.25 inches. The regular drain was to be 1 inch. I am tempted to use the 1.75 asthe main drain but I have been told better.
The Regular drain is cut for a .75" instead of 1"that I was expecting. Will .75 be too little drainage given that I will have 2 drains; one .75" drain in each corner?
I will merge the each .75 tube/pipe into one 1.5" pipe going into the sump Skimmer Chamber
I see no advantage to increase the main drain size from .75 to 1". What do you think?

[Ziggy953]

Typically the larger bulkhead/line is used as the drain line. Sch 40 1" pipe will handle about 600 gph. Depending on what you are planning to do with this system and what kind of return pump you are using you may want to use the 1" as drain and the 3/4" as your return. That is how I have always set my systems up.

[JMorris271]

I believe that is what I shall do. It is my understanding that with that Herbie system at least,the larger diameter hole is suppose to be used for the emergency pipe and the smaller one as the DT drain line . My options involve 2 drain lines One is a 1 inch drain and the other is a ,75 inch line. So there you go. Again, I am just wondering if a .75 inch line is too small for a DT drain line.

[mdaniel2882]

First of all have you seen this thread. It is the origin of the herbie overflow from 10 years ago. it's features are dead silence and flexability. it is designed to run 2 drains in 1 overflow box. not 4 drains in two or two drains in two separate boxes.

NEW plumbing method for an ULTRA QUIET REEF TANK!!!! LONG !!!! - Reef Central Online Community

Next, a 1" PVC pipe will handle MUCH MUCH more than 600 gph when at full siphon. I have one on one of my tanks that handles flow from a sicce 5 pump (about 1200 gph) with the gate valve on the line closed about 1/2 way.

This is the DSA 155 gallon custom tank I got today drilled for a bean animal overflow which is very similar to the herbie. (just the herbie taken another step)
the two outside smaller holes are return lines the 3 in the middle are 1" drain lines. (look for a build thread soon)

The drain lines should not be merged.

you might want to look into a different option for this tank

[JMorris271]

Yes I have read this very LONG thread a while ago.
Due to several recommendations including yours, I have changed design from Herbie to BA. Need to order more bulkheads now to replace the inferior ones that came with the Deep Blue 120 I just received. Shame on them and a waste of Euros for me.
Today is paint day. I need to paint the back of the tank black. Wow! I am a messy painter.