Head Loss

[quilaho]

If the RC head loss calculator indicates:

Using the following input parameters
Friction Factor = .21
Vertical Length = 4
Horizontal Length = .5
Pipe Diameter = .75
Flow Rate = 317
90° Elbows = 1
45° Elbows = 0

Head losses are calculated as
Frictional head loss is 6 foot head or 2.59 psi.
Elevation head loss is 4 foot head or 1.73 psi.
Total head loss is 10 foot head or 4.32 psi.

What does that mean in relation to my GPH comming from the sump back to the tank?

I'm in the learning / planning phases for my first reef and return from sump is the stage I'm at. I'm trying to see what the return rate will be from the Eheim 1250 I already own. The bottom of the sump to the top of the tank will be about 4'. I'm currently planning 3/4" pipe. There will only be one elbow into the tank. A return manifold will be used within the tank.

This will be in a 29g. When I feel I have a complete plan, I will be posting for critiquing prior to build.

Thanks.

 

[plack]

Ya got me ! Welcome to R.F.

From this thread "http://www.advancedaquarist.com/2007/5/aafeature2"

I have tried this Calculator. Although it makes you download and install it, I checked it was virus free! But more importantly it does give you your Gallon per hour!


I entered the info you gave except 5 feet horizontally and any where from zero to 6 90 degree bends ( I have made a version of that manifold to make it you nedd a few !)

I came up with 193 GPH to 188 with six 90º bends without the manifold but just returning to the tank without any 90º bends (wich isnt really do-able without a pump mounted vertically and spa flex tube at the top and that still bending it ! )

Thats only a 3 times the entire water volume changed per hour rate wich is abit slow usually 4-10 times and then the tank inside should have for SPS Tank 25-50 Times the Water Volume including the sump volume!

Merry Christmas !!!

 

[lizardarm]

I wish someone could somehow come up with a calculator that could factor in using an Oceansmotions unit.

 

[quilaho]

Thank you. Expecially for pointing me to an Open Source utility that will actaully run natively under Linux. Linux is all that I run at home.

Let me expand this question a bit and get people's opinion on things I've read.

There seems to be 2 schools of thought when it comes to this. Americans seem to like utilizing one monster pump from the sump to supply most, if not all, the circulation needed (10x generally) in the tank while Europeans use a smaller pump from the sump for filtration purposes (3x) and supplement circulation with power heads or closed loop systems.

The manifold I referenced is geared toward the American style. However, if i ditched the manifold, and used the eheim for the sump return and a couple MJ600 power heads (which I also already own) for circulation, would this make for an effective filtration + cirulation methodology?

This is a beginner reef tank. No SPS are in the forseeable future.

 

[trido]

Total losses are 4.24 feet of head pressure, or 1.83 PSI. with a flow rate of 191 GPH.

When I input your numbers provided, the RC site here without the friction caclulator clearly gave this information on the bottom of the page.

I tend to not believe it due to the fact that I ran a maxijet as a return pump and the numbers told me that it shouldnt have worked after even two feet of head pressure. It worked quite well even after four feet of head pressure. Maybe I just have a miracle maxijet!

 

[Scooterman]

When I input your numbers provided, the RC site clearly gave this information on the bottom of the page.

I tend to not believe it due to the fact that I ran a maxijet as a return pump and the numbers told me that it shouldnt have worked after even two feet of head pressure. It worked quite well even after four feet of head pressure. Maybe I just have a miracle maxijet!

I use a MJ1200 to pump ro water from my tub on wheels to my storage tank, water has to go up almost 7' & the MJ1200 does it. These are some bad little buggers if you ask me!

 

[quilaho]

I tend to not believe it due to the fact that I ran a maxijet as a return pump and the numbers told me that it shouldnt have worked after even two feet of head pressure. It worked quite well even after four feet of head pressure.

The MJ600's would be used within the tank for circulation purposes only. The sump return would be run by the Eheim 1250.

An official measurement from floor to the approximate placement of the hole for return results in 3.5 feet. Using the calculator with 2 90's, a ball valve and 2' of horizontal length results in 209 GPH.

7x return from sump + 11x circulation within the tank sounds like a winner for a beginner to learn from. Well ... to the beginner it does which, most likely, means very little.

Opinions are welcome ...

 

[plack]

"There seems to be 2 schools of thought when it comes to this. Americans seem to like utilizing one monster pump from the sump to supply most, if not all, the circulation needed (10x generally) in the tank while Europeans use a smaller pump from the sump for filtration purposes (3x) and supplement circulation with power heads or closed loop systems."

I originally said

"Thats only a 3 times the entire water volume changed per hour rate wich is abit slow usually 4-10 times and then the tank inside should have for SPS Tank 25-50 Times the Water Volume including the sump volume! "


4-10 times being the approximate min and max for a return pump rate only.
25-50 times being the powerheads/ closed loops(usally this is the monster pump) /and including the return pump.

Some people believe in running the return rate closer to three so in theory the water gets skimmed more, others go for closer to 10X for more air exchange and water flow and hey the skimmer is still skimming.

Just so I am sure youve got it a small side note. Pumps usually dont change much be it 1 or 15 feet of horizontal movment Left to right). However Vertical movement affects it greatly ( up and down). Again just so were clear as you showed .5 Horizontal and thats only 6" up. I think 3.5 feet is the right one in your second post but 2 feet horizontal must mean your not making a circular loop at the top and instead a straight spray bar I take it?

 

[trido]

There seems to be 2 schools of thought when it comes to this. Americans seem to like utilizing one monster pump from the sump to supply most, if not all, the circulation needed (10x generally) in the tank while Europeans use a smaller pump from the sump for filtration purposes (3x) and supplement circulation with power heads or closed loop systems.

I tend to think your misunderstanding this. Most Americans AFAIK generally try for a 10x circulation from the sump and make up the rest with circualtion pumps whether it be from power heads or a closed loop system. I've never seen a reef on the west coast set up any other way. For a reef tank the (American)rule of thumb is to have a minimum of 30x turnover in the display tank. Alot of SPS keepers are shooting for a closer to a 50x plus turnover in their tanks lately. No return pump is going to accomplish that.

The manifold I referenced is geared toward the American style. However, if i ditched the manifold, and used the eheim for the sump return and a couple MJ600 power heads (which I also already own) for circulation, would this make for an effective filtration + cirulation methodology.

That should work fine as long as you have near a 30x tank turnover for your softies

 

[theJ]

I wish someone could somehow come up with a calculator that could factor in using an Oceansmotions unit.

It's pretty much a 90 bend when one side is open I would say, I calculate it in my head loss as a 90, but I have a 2 way that only opens 1 side at a time, other models might be different

 

[quilaho]

I originally said

"Thats only a 3 times the entire water volume changed per hour rate wich is abit slow usually 4-10 times and then the tank inside should have for SPS Tank 25-50 Times the Water Volume including the sump volume! "

My appologies. I did not notice entire water volume. I thought we were talking tank volume so your 3x calculation was not making much sense to me.

4-10 times being the approximate min and max for a return pump rate only.
25-50 times being the powerheads/ closed loops(usally this is the monster pump) /and including the return pump.

OK ... understood.

Pumps usually dont change much be it 1 or 15 feet of horizontal movment Left to right). However Vertical movement affects it greatly ( up and down).

This I fully understand. It's just logical. The calculator had a spot for horizontal so I put it in. At this point, I've done enough reading on this subject to understand they are calculating loss due to friction. It's the same reason they have a spot for couplers, valves, etc. They won't drag it down a lot for my simple application but when doing a more complex application, all those littles would add up to a lot.

... 2 feet horizontal must mean your not making a circular loop at the top and instead a straight spray bar I take it?

I was running the numbers without the manifold as putting power heads inside the tank negated the rational for doing a manifold. The 2' horizontal is because the sump will need to sit next to the stand on the floor (the current stand is not designed in a manner that would allow a tank to be inside it). I had not accounted for that in my original calculations. I still need to account for what will happen inside the tank. I suppose some lockline would be in order to direct the flow.

I tend to think your misunderstanding this.

That would definitely be possible. This is the thread I started at with that line of thought and it then took me to this RC thread. I will confess to not having read the entire RC thread.

It looks like I should plan for a larger pump. Something along a Mag7 or Mag9 looks like it should fit the bill and they are not too expensive.

Thanks for your help.

 

[prbhasson]

Just so you know a mag 7 or mag 9, the manufacturer recommends 1.5 inch piping to get the correct flow from the pump. I have a mag 9 and used 3/4 pipng and it did o.k. Then I switched to the manufacturer's recommendation after I read it in the directions (duh)and it made a huge difference. Pump runs smoother, quieter, more flow, and less wattage draw. My light bill dropped almost $20 a month....

 

[quilaho]

Good to know ... thanks for the info.