Bulkheads & Pipe sizing

[hellsangelbx]

Hey R2R,
I'm starting my new reef tank project. Doing a custom Tank an having my plumbing in the basement with 31ft of head pressure. I wanted to have a max of 10x of turnover even though ideally I'm striving for 5x turnover. As the reef hobby has to be adjustable at any moment I want to have a max flow just incase if I need to adjust up to that. I was wondering what size piping and bulkheads would be ideal for a scenario like this. I'm aiming on 187gal tank to upward of 200gal. I was thinking 2" drain and 1.5" return (or should I go 2" return). I have started my purchase of a return pump which is a ABYZZ A400 ipu which has a 1.5" outlet. R2R Family I appreciate the suggestions back.

 

[fishguy242]

hi ,i would do 2" drain ,start at 1 1/2" and reduce to 1" returns

 

[hellsangelbx]

Do you mean 1” bulkheads

 

[fishguy242]

1" return pipes at tank

 

[hellsangelbx]

Will that be better than 1.5”

 

[fishguy242]

yes, little more pressure =more flow,larger =less pressure more water

 

[Reefer Reboot]

I'd like to clarify this a little bit if I may. Reducing the pipe sizing will increase the pressure which will increase the velocity as the fluid leaves the return port. But at the same time it actually reduces the amount of fluid leaving the return port due to the restriction of orifice size. If the OP wants to get as much total turnover as possible it would be better to stay at the same size or larger from the pump to the tank, including the bulkheads. Going larger would help lessen any tare loss due to directional changes such as elbows. (Sorry for the nerd lingo. I'll stop now.;Stop)

 

[Paulie069]

I'd like to clarify this a little bit if I may. Reducing the pipe sizing will increase the pressure which will increase the velocity as the fluid leaves the return port. But at the same time it actually reduces the amount of fluid leaving the return port due to the restriction of orifice size. If the OP wants to get as much total turnover as possible it would be better to stay at the same size or larger from the pump to the tank, including the bulkheads. Going larger would help lessen any tare loss due to directional changes such as elbows. (Sorry for the nerd lingo. I'll stop now.;Stop)

I love questions like this, I get to learn without having to ask questions lol

 

[JoshH]

I don't step into these types of threads much anymore but personally I'd roll with 1.5-2" from the pump to the tank split to two 1" outlets at the tank itself. My first question is, pipe size aside @hellsangelbx how did you arrive at 31' of head height?

 

[hellsangelbx]

@JoshH thabk for that feed back that sounds like a better strategy of going same diameter of pump and then split up above..
Okay this is how i figured it out I have
8 elbows 1.5" (1ft) = 8ft
18 vertical feet 1.5ft (1ft ea ft) = 18ft
21 horizontal feet (10ft hz =1ft) = 3ft (giving a extra foot here)
Total is 31ft of head pressure. That's how I figured let me know if this is wrong.

 

[hellsangelbx]

I hope the calculations are right,

 

[JoshH]

I hope the calculations are right,

Sorry I missed the notification that you responded, I think you are more than likely much over where you will actually be depending on your flow rate but it doesn't hurt to over estimate. If you don't mind me asking, 18ft is quite the height for going from one floor to the other, is this because your sump will be on the floor?

 

[hellsangelbx]

It’s actually two floors. I have a two family house.

 

[JoshH]

It’s actually two floors. I have a two family house.

Well that makes a lot more sense lol you're actually the first person I've ever come across attempting to run a sump two floors down so congrats on that ;Smuggrin

 

[hellsangelbx]

Yeah i know breaking barriers ;Punch lol. Another question is I would love to return 3 drain lines and 1 return but think it will be tight as I don't have alot of space to run this. Do you think if I were to run 2 drains that will suffice only having one backup.

 

[Reefer Reboot]

Just FYI, if you are going to run a 1.5” return pipe from the pump and put a tee before the tank and then reduce each side to a 1” pipe, you will still be reducing your flow some.

Depending on whether you use Sch 40 or Sch 80 pipe;

Sch 40 1.5” pipe has an ID of 1.59” which gives a cross sectional area of 1.985 square inches. Sch 40 1” pipe has an ID of 1.029” which gives a cross sectional area of .831 square inches. So, two 1” pipes of .831 square inch area x 2 = 1.662 square inch area. A single 1.5” pipe still has a larger cross-sectional area of 1.985 square inches. (A net loss of 16%)

Sch 80 1.5” pipe has an ID of 1.476” which gives a cross sectional area of 1.711 square inches. Sch 80 1” pipe has an ID of .936” which gives a cross sectional area of .688 square inches. So, two 1” pipes of .688 square inch area x 2 = 1.376 square inches. A single 1.5” pipe still has a larger cross-sectional area of 1.476 square inch area. (A net loss of 20%)

This is just something to keep in mind. But on the other hand, you only have 18 feet of vertical head pressure plus a little more for friction and directional fitting loss. So rough “guesstimate”, call it around 20 feet total head pressure. According to the flow chart from Abyzz, that should net you an approximate flow rate of 2,500 GPH (@23’), which would give you a 12.5 x turnover rate for a 200 gallon if you don’t reduce the line.

A two line (Herbie style) drain setup should work just fine.
IMO this should work out great for you!

 

[JoshH]

Just FYI, if you are going to run a 1.5” return pipe from the pump and put a tee before the tank and then reduce each side to a 1” pipe, you will still be reducing your flow some

Exactly my thoughts, reducing with a reducing T 1.5" to two 1" right at the tank would be the best bet for flow and still keep the outlet options open a bit.

Herbie drain would still be a great option as long as he stays around 1.5" for the drains as well.

 

[RobB'z Reef]

I'd like to clarify this a little bit if I may. Reducing the pipe sizing will increase the pressure which will increase the velocity as the fluid leaves the return port. But at the same time it actually reduces the amount of fluid leaving the return port due to the restriction of orifice size. If the OP wants to get as much total turnover as possible it would be better to stay at the same size or larger from the pump to the tank, including the bulkheads. Going larger would help lessen any tare loss due to directional changes such as elbows. (Sorry for the nerd lingo. I'll stop now.;Stop)

Know a little about plumbing do you?

 

[Reefer Reboot]

;Joyful 40 years working in an aerospace hydraulics research and development laboratory!;Hilarious Kinda second nature now.
For @JoshH, why not just stay at 1.5" all the way up to and including the bulkheads into the tank? That way you could always reduce it down after the bulkheads but still leave your options open if you need to stay big?

 

[JoshH]

For @JoshH, why not just stay at 1.5" all the way up to and including the bulkheads into the tank? That way you could always reduce it down after the bulkheads but still leave your options open if you need to stay big?

For me it comes down to a few reasons, none of which are critical but worth considering in no particular order of importance

#1 Larger bulkheads means larger holes in the tank that have to be drilled even lower from the edge pushing the outlets lower down in the water that you need to compensate for on the inside of the tank with longer locline.

#2 Reducers that drop from 1.5" - 1" are almost exclusively white (Aside from Sch80 but I feel the cost of schedule 80 here is not worth it) and therefor hard to hide on the inside of the aquarium even if they are only a thin white ring I know it would drive myself bananas to see that lol (I'm a little OCD when it comes to that kind of thing)

#3 Using the larger 1.5" bulkheads and plumbing will push the aquarium at a minimum of 2-3" further off the wall than using 1" plumbing which can make a big difference in the overall look of the aquarium within your space as well as make things even tighter in the room than need be.

#4 Having dual 1.5" outlets I think would never actually be needed to achieve the higher end of the flow the OP is looking for so I don't see the need to have to worry about upping the outlet size in the future.

#5 Personally I feel the flow gained by doing the 1.5" right to the tank will be negligible and not worth dealing with the potential issues listed above as well as the added costs associated with it. Yes It wouldn't cost a whole lot more to run the 1.5" right to the tank but if I can save $50-75, why not?

Just my thoughts on it, I'm certainly no hydraulic engineer but I think those points are still valid things to consider..