Silent and Failsafe Overflow System

[sleepydoc]

:strooper:

I currently have a Beananimal Overflow on my 100 gallon, and love it. I'm in the midsts of planning a new aquarium right now (~500 gallons), and I want to utilize a Beananimal for it as well. Below is the plan as of now (bear with me as the plan is quite rough still), and a few questions concerning the design...

General Info:
- Aquarium Dimensions: 10' x 3' x 28"H
- External Beananimal Overflow w/ three 1.5" drains running along the 10' back of the tank
- "Fish Room" with sump, filtration, etc. in separate room of the house

Questions:

1. The "Fish Room" (where the sump will be) is on the same floor of the house as the aquarium. The "Fish Room" is located about 10' behind the aquarium, and there are two walls in between the aquarium and the "Fish Room". Should I run the drain plumbing from the aquarium to the sump via running pvc under the house's concrete slab or via the drywall?

I am worried about the amount of back pressure if I choose to run the pvc in the slab. I have the same concern about running the pvc along the flooring through the drywall. Is this a valid concern?

What would you all recommend?

Thanks in advance!

you should talk with metamorphis - he/she is putting together a 500 gallon tank, too.

To (try and) answer your questions:
If you do a bean overflow, going down, under the slab then back up to the sump will be problematic in many ways. Beyond the logistics and expense of setting it up, cleaning and troubleshooting will be difficult and it is more difficult to get a siphon established with a horizontal run; I would have serious concerns about the function of the siphon drain with this configuration.

The resistance of the pipe is a potential concern, but probably not one that can't be overcome. There are sites that go over the equations; It's late and I'm tired, so I can't think of them off hand, but it's definitely doable.

 

[sleepydoc]

What if...
You have a stock dual overflow tank (each side uses 3/4" & 1" bulkheads). Then use one side for 2/3 of the drains and use the other side for the remaining drain and return? Would you have enough room to do this in the overflows? I am thinking 120g+ tanks that use dual overflows, i.e. Deep Sea Pro, Aqueon, etc. I want to be able to put the tank as close to the wall as possible and do not have the convenience of an adjacent fish room. Which drain would be the 3/4"? I am just not comfortable ordering a custom tank or diy on drilling my own.

Doesn't really work too well - the bean animal depends on the drains being in one body of water to function, especially at startup because of the interactions between them. When the water goes over the overflow weir it moves from one body of water to another, so the dual overflow system really had 3 separate bodies (4 if you count the sump). Even if you connect the two with a pipe, there is resistance to the flow of water between the two which can affect the function of the drains.

It may be possible, but I haven't seen anyone who has done it. Try posting the question as a new post in the main area and see if you can find anyone who has had luck with this configuration.

 

[Dandaleh]

Second siphon line would just add unnecessary complexity to a rather simple drain system. For safety, you would have to double up everything. That would be more than just a waste of time and material.

I don't know why you are selling yourself short targeting half the flow you should have this tank.

A 2.5" bulkhead will flow a max-theoretical of 12,759 with a 3' drop, real world friction losses in 2.5" pipe, would reduce this a bit; a 2" bulkhead would flow ~ 8000gph, max-theoretical, so would be a bit small for this tank. My choice would be 2.5" bulkheads and 3" pipe, as well as a pump that could do 10k plus, at the total dynamic head for the system. These tanks are not hobby tanks, and using hobby logic is the wrong approach. (The same logic should be applied to smaller tanks as well.)

Hi there thanks for your reply and hope this message finds you well. I have finalised my system size and the tank will hold max 1050 US Gallons. I have two ABYZZ 400s as returns that willl pump max 5000 USGallons/hr each at the 2 metre head height required. You kindly explained i should go for 2.5inch bulkheads with 3inch pipe (kindly confirm if you still advise the same). My question is why go for larger pipe if the max flow that will go through is dictated by the bulkhead diameter? Is this to make the open channel more effective ? My last question is should the pipes only drop down straight into the sump or is ok to have a 45degree elbow near the end to help get the pipes into the sump which is under the tank? Otherwise i will have to have the sump protude out from under the tanks footprint to get the pipes to drop straight in? Many thanks for you input on this.

 

[Bent]

My standpipes are sitting at about 45 degrees, do they have to be straight up and down for this to work?

 

[KStatefan]

Question on water level in external overflow box. In the drawing below would the water level be at approximately the pink line when the suction drain was adjusted correctly?

 

[Floyd R Turbo]

Kstatefan The water level could be just about anywhere depending on where you set the drain valve. But if that yellow/brown box is your overflow box, you're gonna overflow it on startup.

Siphon line in an external box needs to be as low as possible. Really it doesn't matter if it's 1" or 10" below the water. E drain min 2" from top of box. OC needs to be low as well, top of elbow below the top of the E drain.

More along these lines

But the correction to the above is that you can have the OC at the same level as the siphon, and it won't siphon until the airline gets occluded. The lower you set it relative to the operating water level of the box (which is controlled by the siphon valve) then the more it will flow at that water level.

So my method is to set the siphon all the way down and then the horizontal center of the OC around the point where I want it to operate, so that the water is about 1/2 way up the horizontal circular cross-section of that double 90

JMO

 

[sleepydoc]

My question is why go for larger pipe if the max flow that will go through is dictated by the bulkhead diameter? Is this to make the open channel more effective ? My last question is should the pipes only drop down straight into the sump or is ok to have a 45degree elbow near the end to help get the pipes into the sump which is under the tank? Otherwise i will have to have the sump protude out from under the tanks footprint to get the pipes to drop straight in? Many thanks for you input on this.

Flow resistance imparted by the plumbing is additive, so the total resistance is the resistance of the bulkhead plus that of the pipes, so increasing the size of the pipe without increasing the bulkhead actually does make a difference. In addition, increasing the size of the open channel drain can significantly increase the amount of water it can carry quietly.

45º bends are OK. Horizontal runs can cause problems by preventing the system from purging the air at startup, but most people (myself included) have some 45's and don't have any issues.

 

[KStatefan]

Kstatefan The water level could be just about anywhere depending on where you set the drain valve. But if that yellow/brown box is your overflow box, you're gonna overflow it on startup.



JMO

Thanks. The box does not matter in this was just on that part of the drawing when i copied it to the jpeg.

 

[Bent]

Flow resistance imparted by the plumbing is additive, so the total resistance is the resistance of the bulkhead plus that of the pipes, so increasing the size of the pipe without increasing the bulkhead actually does make a difference. In addition, increasing the size of the open channel drain can significantly increase the amount of water it can carry quietly.

45º bends are OK. Horizontal runs can cause problems by preventing the system from purging the air at startup, but most people (myself included) have some 45's and don't have any issues.

That's all I needed to hear. Gratzi

 

[sleepydoc]

My standpipes are sitting at about 45 degrees, do they have to be straight up and down for this to work?

I just can't figure out if I'm looking at that picture straight... :spin2:

It should be fine. The main issue is whether the siphon channel can purge the air. This depends on the configuration of the plumbing, the pipe size and the flow. As I said in the post above almost everyone has at least a short stretch of angled pipe and doesn't have issues with it. Horizontal stretches are the big problem.

 

[sleepydoc]

Really it doesn't matter if it's 1" or 10" below the water. E drain min 2" from top of box. OC needs to be low as well, top of elbow below the top of the E drain.

Well, that depends on the flow and your pipe size. If you have it too close to the surface, it will tend to suck air from vortices that form from the surface. You also need to make sure it far enough off the bottom of the overflow box so it doesn't restrict flow.

 

[Floyd R Turbo]

Besides that, yes. I was speaking in vague generalities in order to provoke a response. And it worked

 

[Dandaleh]

Flow resistance imparted by the plumbing is additive, so the total resistance is the resistance of the bulkhead plus that of the pipes, so increasing the size of the pipe without increasing the bulkhead actually does make a difference. In addition, increasing the size of the open channel drain can significantly increase the amount of water it can carry quietly.



45º bends are OK. Horizontal runs can cause problems by preventing the system from purging the air at startup, but most people (myself included) have some 45's and don't have any issues.

Ok thanks for that . What do you think regarding 2.5inch bulkheads going to 3inch pipe? Im trying to find out how much flow this will handle ? The pumps I have will produce 10k gallons / hour at 2m head height

 

[sleepydoc]

That should be fine - a 2.5" pipe can theoretically flow about 18,000 GPH at a 2 m head height, so you have plenty of margin for error

 

[Dandaleh]

Did you mean 3" pipe ? Uncleof6 recommended a 2.5" bulkhead and 3" pipe ?

 

[Dandaleh]

Just want to make sure I'm not going wrong with those sizes?

 

[sleepydoc]

Did you mean 3" pipe ? Uncleof6 recommended a 2.5" bulkhead and 3" pipe ?

I ran the calculations with 2.5" pipe. 3" pipe will flow even more.

Note that I have no experience with tanks of this size or systems using this kind of flows. As uncle said, this is beyond the scope of a normal hobby tank, so any advice should be taken with that caveat.

 

[Dandaleh]

Ok fine , so I could do 2.0 inch bulkhead with a 2.5inch pipe which would handle up to 18000 gallons per hour ? Out of interest do you refer to a tool or website that's does the flow calc ? Yes it's a bigger tank but the principle is the same , just need to ensure the pipes can handle enough flow for the pumps

 

[Dandaleh]

Appreciate your help on this

 

[sleepydoc]

There's a head loss calculator on RC's home page. It probably won't be much help, though. Head pressure is dependent on flow, and flow is dependent on your pumps flow/pressure characteristics, so most head loss calculators use an iterative approach based on known pressure-flow characteristics for a given pump, and your pump and flow rates likely won't be in the calculator.

In terms of flows for a siphon, bean animal has a calculator on his web site that will give a rough estimate of flow through a straight siphon. It ignores any elbows, bulkheads, etc, so it tends to estimate high, but it will give you a place to start