plumbing question

[saltyESQ]

As I am about to purchase all my bulkheads, I just realized something.

Does it matter or make a difference if I get them threaded on the outside or inside?

I was planning on getting them threaded on the outside.
(this is for a closed loop to a dart)

I will be purchasing a 2 inch bulkhead.

Then two 3 inch bulkheads for the overflow.

 

[IsaaX]

Most people use 3/4" or 1" bulkheads. What is your reason for using such big bulkheads?

 

[IsaaX]

I forgot to ask, if the tank is FOWLR, what purpose would the closed loop serve? Will you be changing it to a reef in the future?

 

[Yinger]

why are you using 2 3 inch bulkheads? I didn't think they even made them this big. Are you really going to be pushing 20,000 gallons per hour through your sump? And what do you mean by threaded because they are all threaded on the ouside where the fastner goes on. I don't believe anything bigger than a 3/4 inch has threaded/threaded on the inside. Maybe 1 inch.

 

[IsaaX]

The only bulkhead I know of (at this time, but might be others)that you can thread a fitting to on the outside of it (in the back) is a 1/2" bulkhead in which you can screw a female 3/4" fitting to it.

 

[saltyESQ]

First, while I am going to have a fowlr tank I want good circulation to keep nitrates down (so I have less work),
My tank is glass and the closed loop drain is drilled at 2inch
and I have 2 overflow holes in my overflow box, each of them is 3inches. (I know they make 3inch bulk heads bc I called vivid aquariums and they had them in stock)

When I meant threaded, I have seen the threading both on the inside of the tube attached to the bulkhead and the outside. ( I think I have an answer to this after reading comments)

 

[818]

The threaded/slip bulkhead choice is up to you. What type of plumbing and how you want it to look. If you get them threaded inside you can reduce them for the pumps intake at 1.5(I think thats what darts have?) Its really up to you.

 

[Yinger]

If you want to keep nitrates down, i'd suggest getting a big and efficient skimmer. Honestly, nitrates don't matter as much in a FO tank. Hmm... is your overflow going to fit 2 3 inch dursos, or are you not planning on having those?

 

[IsaaX]

<a href=showthread.php?s=&postid=8124177#post8124177 target=_blank>Originally posted</a> by saltyESQ
First, while I am going to have a fowlr tank I want good circulation to keep nitrates down (so I have less work),
My tank is glass and the closed loop drain is drilled at 2inch
and I have 2 overflow holes in my overflow box, each of them is 3inches. (I know they make 3inch bulk heads bc I called vivid aquariums and they had them in stock)

When I meant threaded, I have seen the threading both on the inside of the tube attached to the bulkhead and the outside. ( I think I have an answer to this after reading comments)

Ok that explains it. If it were me, I'd thread on the inside of the bulkhead or do a slip fit since it's a lot more common to find fittings to do it that way. Trying to find a adapter to thread on the outside of a 2" - 3" bulkhead and bring it back down to the appropriate size for the rest of the plumbing (2" - 3") would be more troublesome if that type of adapter even exhists. It would be more ideal and much easier to thread or slip in the inside of the bulkhead.

 

[saltyESQ]

<a href=showthread.php?s=&postid=8124204#post8124204 target=_blank>Originally posted</a> by Yinger
If you want to keep nitrates down, i'd suggest getting a big and efficient skimmer. Honestly, nitrates don't matter as much in a FO tank. Hmm... is your overflow going to fit 2 3 inch dursos, or are you not planning on having those?


here is the pick of one of the 2 overflow drains

I think I can fit 2 duroso pipes in there, dont ya think?

Here is a pic of both drains

I am planning on also having some good filtration, an asmg4x with recirc and gate valve, refuge, 200lbs of LS, and 150lbs of LR.

one of the overflow drains will feed the skimmer

 

[Fmellish]

"I have seen the threading both on the inside of the tube attached to the bulkhead and the outside."

LOL.

dude, they are always threaded on the outside, how else would the collar screw on?

As far as the inside, the 3 common types are
- Slip*Slip
- Thread*Thread
- Thread*Slip.

I prefer Thread*Slip. This is threaded on the wet side and slip on the dry side. This allows you the flexibility of using screw in nozzles and adapters on the wet side, and the reliability of using glue on the dry side.

Hope that helps.

Cheers
Josh

 

[Yinger]

the holes are 3 inches, the bulkheads you'll need is probably 2 inches.

 

[saltyESQ]

<a href=showthread.php?s=&postid=8124476#post8124476 target=_blank>Originally posted</a> by Fmellish
"I"

LOL.

dude, they are always threaded on the outside, how else would the collar screw on?

Josh

:lol: you know when I think about it, you are correct

 

[Fmellish]

The hole looks about 2.75". With holes your size you may be able to do a 2" or 2.5" bulkhead, but not a 3".

And it doesn't look like much room was left between the glass and the holes. The collars will be a tight fit.

Two dursos might be tough. A Durso takes up a lot of space. But if one fits, then two should fit since you can have them facing opposing directions.

Keep in mind, you can have a really large drain diameter, but you'll be limited to the amount you can drain by the perimeter length of your overflow weir and the spacing and width of your overflow teeth.

Hope that helps.

Josh

 

[saltyESQ]

<a href=showthread.php?s=&postid=8124503#post8124503 target=_blank>Originally posted</a> by Fmellish
The hole looks about 2.75". With holes your size you may be able to do a 2" or 2.5" bulkhead, but not a 3".

And it doesn't look like much room was left between the glass and the holes. The collars will be a tight fit.

Two dursos might be tough. A Durso takes up a lot of space. But if one fits, then two should fit since you can have them facing opposing directions.

Keep in mind, you can have a really large drain diameter, but you'll be limited to the amount you can drain by the perimeter length of your overflow weir and the spacing and width of your overflow teeth.

Hope that helps.

Josh

the holes are actually 3inch.and have measured them several times.

There is actually a lot of distance btwn the glass and holes, the overflow is huge, both in lenght and width

the opening for the overflow is the full lenght of the overflow box, which is 16.5 inches and about 2 inches tall

 

[818]

Josh, you are wrong. Spears makes some that are threaded only enough for the collar to screw on. Then the rest of the bulkhead is a slip.*Though these are specieal order*

You can fit 2 Dursos easy. Just have the facing away from each other.

 

[Fmellish]

<a href=showthread.php?s=&postid=8124686#post8124686 target=_blank>Originally posted</a> by My F1sh R D34D!
Josh, you are wrong. Spears makes some that are threaded only enough for the collar to screw on. Then the rest of the bulkhead is a slip.*Though these are specieal order*

I don't see how your premise leads to your conclusion.

I claimed there are threads on the outside for the collar to screw onto, and you are claiming the same. So how am I wrong? The discussion was not regarding the amount of threading, but whether or not threads are present.

Thanks for agreeing with me.

 

[818]

Mike wants to know if he can get something slip on the outside as well. I guess I just added your thesis, thats all.

 

[ReefMeister2]

Damn, you guys are giving me a headache!

I've been putting off making "The Lazy Reefmeister Episode IV" for some time now, but I think I've at least narrowed down the subject matter: "Plumbing for Dummies, Reefmeister Review 101" :lol:


SaltyESQ,
I'll get shoot you out some more detailed answers in a bit

 

[ReefMeister2]

Ok here goes:

1) The "size" designation of the bulkhead fitting has NOTHING to do with the outside diameter of the bulkhead...thus has NOTHING to do with the size hole that the bulkhead will fit into. The bulkhead "size" refers to the standard size pipe that the bulkhead is designed to accomodate.
So...Your 3" diameter hole will accomodate a 2" bulkhead fitting (to accomodate 2" pipe)

2) The designations: slip x slip, etc. refers to the inside configuration of the bulkhead fitting, starting with the flange side.
So....a "thread x slip" bulkhead refers to one that has threads on the inside nearest the flange, but is smooth on the inside at the nut end. The smooth (slip) surface is designed to accomodate a standard sch 40 PVC pipe with PVC cement.

3) As mentioned, the outside of a bulkhead fitting is always threaded to accomodate the locking nut....HOWEVER....
(I hate to even mention this, it only complicates matters)
bulkheads that have "white" nuts have standard outer threads and will thus allow you to thread fitting (such as ball valves) to the "outside" of the bulkhead. For example, a 1" bulkhead fitting (with white nut) will allow you to screw a 1-1/4" ballvalve to the outside of the bulkhead.
Those with "black" nuts have slightly oversized threads that won't allow anything else but the nut to screw onto it.

The obvious advantage of threading items to the "outside" is that you gain capacity by increasing to the next size of plumbing fittings. Remember, a 1" bulkhead fitting does not mean that it has a 1" hole....it means it is meant to accomodate 1" inside-diameter PVC pipe, but the "outside" diameter of that pipe is larger, yes? So guess what? the inside hole of a 1"
(economy) bulkhead fitting is actually more than 1-1/4". Get it? Go grab one, measure it, and you'll see!
A 3/4" bulkhead will allow a 1" ballvalve.....a 1-1/2" bulkhead fitting will accomodate a 2" ballvalve (threaded to the outside), and so forth.
Its like MAGIC, I tells ya!

4) I know this question is coming, so lets get it outa-the-way.
Yes, you CAN mount bulkheads EITHER way: upside down, right-side up, etc. The flange side of the bulkhead (and gasket) is generally installed on the liquid side, however.....there are ways to mount it in reverse. For instance, you may have a situation where "clearance" is an issue and you'd rather have the flange on the outside of the tank instead of the threaded shank. In this case I like to use gaskets on BOTH sides of the bulkhead just for reassurance. If the nut is "notched" (as many are) I will either sand off the notches to make it smooth (so not to bunch up the gasket) or I will make a plastic "washer" of appropriate size to act as a buffer between the nut and second gasket.




Have I confused you enought yet????

If not, I can start talking about Schedule 80 bulkheads (all different rules than what I explained above) :lol: