1,000 GPH

<a href=showthread.php?s=&postid=10161954#post10161954 target=_blank>Originally posted</a> by sm007h
the pumps we've been talking about are ~$150+
I don't remember mentioning an eheim 1250?

the eheim 1250 is rated at ~300 ft @0 head. and has a max head of 6.5 ft...if that's enough flow for your needs then that'd be the pump to get. Eheims are great little pumps. If you get a larger eheim, however, you can dial it back without damaging the pump, which will ensure you have enough flow rather than too little.
 
<a href=showthread.php?s=&postid=10162296#post10162296 target=_blank>Originally posted</a> by sm007h
I don't remember mentioning an eheim 1250?

the eheim 1250 is rated at ~300 ft @0 head. and has a max head of 6.5 ft...if that's enough flow for your needs then that'd be the pump to get. Eheims are great little pumps. If you get a larger eheim, however, you can dial it back without damaging the pump, which will ensure you have enough flow rather than too little.

Do all Eheims have that option?
 
<a href=showthread.php?s=&postid=10155697#post10155697 target=_blank>Originally posted</a> by sm007h
If you must know where I came up with that, a rule of thumb is to add a ft of pressure per 90 elbow and a few feet of vertical height since I'm assuming you use a normal height stand. I don't consider your pipe diameter, but I'm going to have to guess that it's not 2".

There are charts that show exactly what fittings add as far as pressure goes. I can assure you, a 90' elbow is nowhere near 1 ft of head. Its pretty much the equivalent of 1 ft of horizontal run.


There IS a consensus that 20x sump-to-tank is much higher than needed, and 50x through your sump is absurd.
 
<a href=showthread.php?s=&postid=10163591#post10163591 target=_blank>Originally posted</a> by RichConley
If you're going to give advice, atleast understand what you're giving advice on.

This thread was going just fine without any personal insults.
If insults over facts are best way you can convey your opinion, then why should we listen to it?

If you wanted to be convincing in the slightest, why not post the charts you're referring to? Your "assurances" aren't going to cut it...

...especially since you stretched the truth on what anyone was saying.

No one claimed that 20x sump turnover was fine.
20x sump turnover would be if his "1000 GPH" pump were pushing what it claimed on the label and had 0 ft head pressure :O

Nice try, though.
First hit on google:
Keep in mind that every turn the water takes as it returns to your aquarium increases head and reduces flow. Keep tight turns to a minimum. A good rule of thumb if using 1/2" to 1" I.D. tubing is to add one to two feet of head for every 90 degree elbow or tee on the return side of the pump. The smaller the diameter of the tubing, the MORE head you should add.

-- http://www.aquariumpros.com/articles/headpress.shtml

I already pointed out that he's using a 3/4" 90 degree elbow.
You implied that *all* elbows are the same...when in fact they are not.

That's how to refute an argument with *facts* rather than insults.
 
How many "rules of thumb" in this hobby are actually correct? 5%?


http://www.watergarden.com/catalog/_pumps/friction.html


theres one chart. Like I said, elbows CAN NOT be directly translated to head loss. They can be translated to equivalent runs of straight pipe with friction loss.

In this specific case, a 90' elbow results in .4 feet of head, not 2. If he were to move up to 1" pipe, it would result in .1 ft of head.



WHERE did I imply that all elbows are the same? I most certainly did not.




An interesting note, is that in a LOT of cases, two 45' elbows are actually worse than a single 90.
 
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<a href=showthread.php?s=&postid=10163716#post10163716 target=_blank>Originally posted</a> by RichConley
How many "rules of thumb" in this hobby are actually correct? 5%?


http://www.watergarden.com/catalog/_pumps/friction.html


theres one chart. Like I said, elbows CAN NOT be directly translated to head loss. They can be translated to equivalent runs of straight pipe with friction loss.


WHERE did I imply that all elbows are the same? I most certainly did not.

What *exactly* is your point?
Are you debating whether he has 4ft or 6ft head?
Or just trying to prove me "wrong" in my *estimation* (thereby ignoring the general, and correct, point that his pump is not pushing 1000 GPH due to head loss)?

The chart you posted illustrates that a 3/4" 90 is equivalent to 2 straight feet of friction. So what does that do to his head loss? And if you're going to calculate it all out then might as well figure in the tubing and couplings and loc line splits/dual outlet, right?


Short and sweet version: how much head loss do you think his pump is pushing against?
 
<a href=showthread.php?s=&postid=10163716#post10163716 target=_blank>Originally posted</a> by RichConley
WHERE did I imply that all elbows are the same? I most certainly did not.

I can assure you, a 90' elbow is nowhere near 1 ft of head

According to formal logic, your sentence implies *all* elbows since you didn't state differently.

I don't know if you're itching for a fight or bored, but I'm not going to let you drag me down into something that isn't going to be profitable to anyone. So unless you have any information to give rather than bickering over petty points, I don't see much point in responding any further.
 
54" to the top of the tank, minus 12 for sump height, so 42 inches. With all fittings and such, maybe 10' equivalent of horizontal run (2' vertical equivalent).

Thats 66", or 5.5 ft. The GenX4100 moves roughly 750 gph at 6 ft. So hes got maybe 800gph, or 15x turnover going tank-sump, or 40x through the sump, which is entirely too much.
 
<a href=showthread.php?s=&postid=10163777#post10163777 target=_blank>Originally posted</a> by sm007h
According to formal logic, your sentence implies *all* elbows since you didn't state differently.


Saying something about all elbows does not imply that all elbows are the same.

In almost every single situation, and elbow does not equal 1 foot of head height. That doesnt mean they are the same.
 
Your first post in this thread was an insult directed to me.
The rest of your posts are attempts to "prove" me wrong.
I'm not sure what your intent is, but you're not providing helpful information...I can't keep correcting your misinformation all day.

The figures you keep using are estimated on the low or high end, depending on which one will help your point more. Your math above isn't even accurate, and neither are the base numbers you're using for a Gen-X 4100 pump!

GX4100

Gen-X Submersible water pump

1085 GPH
9.2ft maximum lift
UL approved
Ceramic Shaft
1 year guarantee against manufacturer defects.
PSI Rating 3.98
5/8" and 1" ID Hose fittings included.
750 gallons at 3' Head
650 gallons at 5' Head
Power Consumption 70 Watts

-- http://www.reefexotics.com/gen-x_submersible.htm

His tank turnover is closer to 10x @ 5ft head...ironically, you claimed I was wrong in my calculation but you came up with 5.5ft as opposed to my off the cuff 6ft?

Are you going to apologize for slamming me for not knowing what I was talking about but coming up with the same amount of head pressure anyway?
 
<a href=showthread.php?s=&postid=10163865#post10163865 target=_blank>Originally posted</a> by sm007h
Your first post in this thread was an insult directed to me.
The rest of your posts are attempts to "prove" me wrong.
I'm not sure what your intent is, but you're not providing helpful information...I can't keep correcting your misinformation all day.

The figures you keep using are estimated on the low or high end, depending on which one will help your point more. Your math above isn't even accurate, and neither are the base numbers you're using for a Gen-X 4100 pump!



-- http://www.reefexotics.com/gen-x_submersible.htm

His tank turnover is closer to 10x @ 5ft head...ironically, you claimed I was wrong in my calculation but you came up with 5.5ft as opposed to my off the cuff 6ft?

Are you going to apologize for slamming me for not knowing what I was talking about but coming up with the same amount of head pressure anyway?

My point is that you're using "guesses" instead of actually figuring out what it is. Yeah, you were close, but that doesnt mean you were right. He'd be much better served understanding what was going on here, instead of listening to your guesses, based on false premises (1 elbow equals 1 foot). Even a blind squirrel finds a nut sometimes. According to you, he could add 3 more elbows and the pump would shut off. We KNOW thats not the case.

Look, my initial post was insulting. Thats why I removed it about 10 seconds later. WELL before you posted.


I really hate when people use "rules of thumb" that are flat out false, and you continue to do that.
 
LMAO, actually, Rick, I used a "rule of thumb" *once*...that I "continue to do that" is a figment of your imagination...a straw man you constructed to beat on in order to win an argument no one else was interested in having.

You couldn't have edited your post *before* I replied because I quoted your insult.

The fact that I was "close" (well, off by 6 inches, and that's not saying that your calculations are absolutely correct...unless you *are* claiming that to be the case) *does* mean that I was right...much to your disgust apparently.

Yes, I used a guestimate to figure out that his pump wasn't really pushing 1000 GPH through the lines, which is all I set out to do. I couldn't very well do anything else because he didn't tell us his pump and the manufacturer doesn't publish flow rates. You coming in on the tail end of a conversation where the footwork was already done and insulting the person who did most of the calculations demonstrates your need for attention, not that you actually know what you're talking about.

All of this is compounded by the fact that you didn't inform the OP in the least on how to understand "what was going on here."

And to top it off, you just keep spewing misinformation.
The fact of the matter is, even using your .4 ft of head loss per 3/4" 90 elbow, that his pump would then be pushing against 8 ft of head pressure if he added three more elbows.

And Rick, much to your displeasure, that would indeed mean that his pump would shut off...because it's rated at a maximum of 8.7 ft of head pressure and you haven't even figured in the loc-line or the piping it'd take to connect the three elbows!

So everyone reading this can now see that you are rude and wrong about just about everything you posted so far. You're unwilling to accept an alternate viewpoint, and you evidently can't apologize even when you are rude and wrong.

That's not the type of person I want to listen to or interact with. I wouldn't trust a scrap of advice from someone like you even if you turned out to be right on occasion (employing your "blind squirrel" analogy) and, consequently, you're the first person on my ignore list.

Have a nice day :)
 
<a href=showthread.php?s=&postid=10164301#post10164301 target=_blank>Originally posted</a> by sm007h
LMAO, actually, Rick, I used a "rule of thumb" *once*...that I "continue to do that" is a figment of your imagination...a straw man you constructed to beat on in order to win an argument no one else was interested in having.

You couldn't have edited your post *before* I replied because I quoted your insult.
Look at the timestamps. I edited within 1 minute of posting. Notice theres no edit timestamp. You posted 6 minutes later...so yeah, I edited before you posted.

The fact that I was "close" (well, off by 6 inches, and that's not saying that your calculations are absolutely correct...unless you *are* claiming that to be the case) *does* mean that I was right...much to your disgust apparently.

No, it doesnt. The number isnt what matters, its the process. You stated that "elbows add 1' of head height," which is false. IE, you got the right number, but got it the wrong way. It was a lucky guess, no more, and doesnt add anything to the understanding of the process.
And to top it off, you just keep spewing misinformation.
The fact of the matter is, even using your .4 ft of head loss per 3/4" 90 elbow, that his pump would then be pushing against 8 ft of head pressure if he added three more elbows.

And Rick, much to your displeasure, that would indeed mean that his pump would shut off...because it's rated at a maximum of 8.7 ft of head pressure and you haven't even figured in the loc-line or the piping it'd take to connect the three elbows!

Again, you're proving you have absolutely no idea what you're talking about. As you increase the fittings, total friction increases. That slows down the velocity, lowering the coefficient of friction. Adding three elbows will NOT shut off the pump. It'll make less water come out, but you can add fittings till the cows come home, and it wont shut off. The only thing that will really shut off the pump, is going above that max head.

Each time you add a fitting, you slow down the water, which decreases the difference that a fitting makes. You can add 150 fittings, and they wont have any noticible effect over addign 100 fittings. Why? Because the water is moving so slow at that point that theres almost no friction loss.

You keep proving that you DO NOT UNDERSTAND how this works.
 
As an example, a Mag5 at 5' of head is 250gph.

Add 100 ft of horizontal plumbing, and 100 elbows, and its still at 185gph. Why? Because water is moving slow enough that friction isnt making any real difference.
 
hahaha, I couldn't help myself :D
I had to read what you posted because I am bored...and avoiding grading my students' papers!

Thankfully, I was not disappointed because your responses were as humorous as the last ones!

Look, Rick, it's all rather simple.
You couldn't possibly have edited your post before I replied because I quoted your post! I have no idea why there is no edit stamp, but my post is sitting right there in black and white with your statement in it that you went back and edited out.

So you see, Rick, you posted it, I quoted it, and then you edited it out. If you edited it out before I came along, how do you explain me quoting it? You even admitted that you insulted me and then edited it! LOL! It doesn't get much better than this, I'd say.

Now on to the topic at hand...
Rick, how do you come up with the silly notion that *I* said elbows add a foot of head pressure? The numbers were coming from reefcentral's own head pressure calculator and I cited a source suggesting that people add 1 to 2 feet of head pressure as a rough estimate when figuring head pressure.

I know it stings, I've been wrong before...but I don't go insulting the people who were right :D That's just silly...and juvenile.

You're trying so hard to prove me wrong, and that you alone are the arbiter of relevant and correct information that you are stepping all over yourself!

I used your own numbers to come up with 8 ft of head pressure. Then I quoted the OP's numbers of the pump's max head pressure. Right in your response you argue that the pump won't shut off until it reaches the max head...

...did you notice that I pointed out you only had .7 ft left? and that you hadn't bothered to calculate the union, or the loc-line, or the dual split, or even what it will take to connect three elbows (assuming you don't glue them flush! Although, that would ignore the fact you would have a 270 degree elbow and we *don't* want to go there, do we :D)? Now, if that doesn't come to .7 ft of head, why don't you whip out your handy dandy calculator and *prove* me wrong?

Prove me wrong that his pump won't be facing its max 8.7 feet of head pressure and that it won't shut off.

Prove it to us with some numbers instead of insults that I don't understand what is going on :D

Because then, Rick, you will be "The Winner" and that is, after all, what this is all about, right? Because it apparently didn't have much to do with adding to the quality of the information of the thread...


@SSalty,
On the plus side, you now know what you have to do :)
Just add three more elbows and viola! your microbubbles should be gone ... ;)
 
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<a href=showthread.php?s=&postid=10164673#post10164673 target=_blank>Originally posted</a> by sm007h
hahaha, I couldn't help myself :D
I had to read what you posted because I am bored...and avoiding grading my students' papers!

Thankfully, I was not disappointed because your responses were as humorous as the last ones!

Look, Rick, it's all rather simple.
You couldn't possibly have edited your post before I replied because I quoted your post! I have no idea why there is no edit stamp, but my post is sitting right there in black and white with your statement in it that you went back and edited out.

So you see, Rick, you posted it, I quoted it, and then you edited it out. If you edited it out before I came along, how do you explain me quoting it? You even admitted that you insulted me and then edited it! LOL! It doesn't get much better than this, I'd say.

Because you clearly dont understand how simple internet bulletin boards work. You grabbed the text before I edited, IE, you hit quote. Then you took 6 minutes to type, and then post. I had already edited the post at that point. Basically, I edited before you posted, which is clearly, EXACTLY what I said. Clearly you lack the simple understanding of how bulletin boards work. There is no edit stamp because I edited the SAME MINUTE I POSTED.


Now on to the topic at hand...
Rick, how do you come up with the silly notion that *I* said elbows add a foot of head pressure?
POST

That post, where you clearly said: "a rule of thumb is to add a ft of pressure per 90 elbow"
The numbers were coming from reefcentral's own head pressure calculator and I cited a source suggesting that people add 1 to 2 feet of head pressure as a rough estimate when figuring head pressure.

We've gone over this... the calculator doesnt work all that well.



...did you notice that I pointed out you only had .7 ft left? and that you hadn't bothered to calculate the union, or the loc-line, or the dual split, or even what it will take to connect three elbows (assuming you don't glue them flush! Although, that would ignore the fact you would have a 270 degree elbow and we *don't* want to go there, do we :D)? Now, if that doesn't come to .7 ft of head, why don't you whip out your handy dandy calculator and *prove* me wrong?

Prove me wrong that his pump won't be facing its max 8.7 feet of head pressure and that it won't shut off.

Theres no reason to "PROVE" you wrong. This is a simple optimization problem that you do not understand. Your ability to argue doesnt make you any less wrong.

The way flow is calculated is by calculating friction losses at full velocity. Then you substitute the new velocity, and recalculate. You keep iterating until the difference gets to be negligible.

The pump wont be anywhere near its 8.7ft, and thats that.

If you really want, If you can list every fitting there, in the order theyre in, and exactly every length of pipe, I will do the calculations out for you, but you'll probably just get bored as I start iterating, because to properly do it out, you need to keep iterating until the difference hits 0, and thats going to be thousands of calculations.
 
SSalty,

I may have no idea what I'm about to suggest, given that I lack the simple understanding of how an internet forum operates, much less plumbing :D, but I *think* you should calculate your head pressure *before* selecting a pump...

...call me crazy, misinformed, or just plain stupid (that about covers it, right Rick?), but you'll need to know what you're up against before you can select the right pump!

So, given that Rick is bored, eager to prove me an ignoramus, and offering to do these superooperduper critical calculations by hand on his slide ruler, and my guestimations not only annoy him to the bitter end, but they in most probably will result in a pump SNAFU Kaboomy!...please oblige us with a list (in order) of your plumbing arrangement?

If you would, sir? ;0
 
Lets do out a simple example here:

Mag 5, 0' vertical run, 10 elbows, 3/4". According to your 1 elbow=1ft, the pump should shut off.

10 elbows is essentially 20 feet of straight pipe (friction-wise).

So, we do out our numbers.

20ft * 15ftloss/100ft = 3ft of friction loss.

At 3ft of head, a Mag5 produces 380gph. So now we do the calculation again, based on 380gph.

20ft * 9/100 = 1.8 ft of loss.

A mag5 produces about 425 gph at 1.8ft. So you do the calculation over at 425gph

20ft * 10.5/100 = 2.10 ft of loss.

You keep going until the numbers converge. In this case, its going to be about 2 feet of loss, for 415 or so gph.

Going out to 100 elbows is going to result in the same thing... less waterflow, but the pump will not shut off.

I'm going to make the assumption of 120gph for 100 elbows

200ft * 1.02/100 = 2ft

At 2ft of headloss, the mag5 makes 415 gph. That means my assumption was too low.

200ft * 10.5/100 = 21ft, which is way too high.

So lets try 300gph

200ft * 5.73/100 = 11.5ft of head, which is the shutoff head of the pump. So we know its between 300gph and 120 gph.

Lets try..200. I'm going to have to extrapolate and say that friction losses are 3ft/100ft of run at 200gph for 3/4" pipe.

200*3/100 = 6ft of head, for 180gph. That means its between 180gph and 200gph.

So, if you put 100 elbows on a mag 5, it'll still pump 190gph.
 
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