I see that some people have put there returns through the back of there tank on the side of the calfo and other have gone over the top of the tank with the returns and some have even gone through the calfo to up and over into the tank what are the benifits to each? besides placement wouldn't having them in certain area reduce the amount of water that will get sucked back into the tank in a power off situation?
Silent and Failsafe Overflow System
- Thread starter JohnL
- Start date
BeanAnimal
Premium Member
This should help:
BeanAnimal
Premium Member
Yes, the flow rate of a siphon is directly related to the amount of head pushing (pulling!) the water through the pipe.
betoballer1
New member
I might consider doin this in the future
BeanAnimal
Premium Member
I am not quite sure I understand the question with regard to your setup... but i will answer your first question.
The "head height" in the table above denotes the total head on the siphon and is measured from the water line at the intake to the discharge of the standpipe. The table only works if the standipe is truly acting as a siphon (not a 2-phase mixture of air and water). The "bulkhead" size denotes the smalles diameter in the standpipe (usually the bulkhead). The table is a rough "best case" calc. There are a dozen variables that can make things slightly or vastly different.
The "head height" in the table above denotes the total head on the siphon and is measured from the water line at the intake to the discharge of the standpipe. The table only works if the standipe is truly acting as a siphon (not a 2-phase mixture of air and water). The "bulkhead" size denotes the smalles diameter in the standpipe (usually the bulkhead). The table is a rough "best case" calc. There are a dozen variables that can make things slightly or vastly different.
TheFishMan65
New member
Are those head height in the chart in feet. thanks
BeanAnimal
Premium Member
None worth getting into within our frame of reference, other than friction. Head in a resevoir above the "pipe" has no friction, fluid falling through the pipe is affected by friction.
Barfly
Custom User Title
Ok, well I read through this WHOLE thread and my eyes have had it from looking at the computer screen. Anyway, getting ready to order a custom drilled tank tomorrow and had a couple of questions.
My tank is only going to be viewable from the front. and will have about 6" on each side of the front covered. It is going to be 72"x18"x24" (LxWxH). I plan on running the return lines through 1 of the sides of the tank because it will be only about 1" from the wall so I have no room. My idea for the weir was to do better than coast to coast. I figured I would run a box around the front and 2 sides stopping it about 6" front the front of the tank on both sides. On the side that will not have the plumbing and the back, I was thinking about a box that would be stick out about 2" and only be about 2" - 3" deep. On the side that the plumbing is going to be on, I was thinking it could stick out 4" - 5" and be about 5" deep.
Do you think a setup like this will work?
Using your plans what is the minimum width (from tank to weir) the weir needs to be in order to easily remove the plumbing parts if needed?
Also, What is the minimum depth the box needs to be so I will not need to modify the parts?
I plan on using a CL circulation system for high volume flow, How many gallons per hour should I be shooting for in the sump return?
Thanks for any help!:fun4: I need it!
My tank is only going to be viewable from the front. and will have about 6" on each side of the front covered. It is going to be 72"x18"x24" (LxWxH). I plan on running the return lines through 1 of the sides of the tank because it will be only about 1" from the wall so I have no room. My idea for the weir was to do better than coast to coast. I figured I would run a box around the front and 2 sides stopping it about 6" front the front of the tank on both sides. On the side that will not have the plumbing and the back, I was thinking about a box that would be stick out about 2" and only be about 2" - 3" deep. On the side that the plumbing is going to be on, I was thinking it could stick out 4" - 5" and be about 5" deep.
Do you think a setup like this will work?
Using your plans what is the minimum width (from tank to weir) the weir needs to be in order to easily remove the plumbing parts if needed?
Also, What is the minimum depth the box needs to be so I will not need to modify the parts?
I plan on using a CL circulation system for high volume flow, How many gallons per hour should I be shooting for in the sump return?
Thanks for any help!:fun4: I need it!
Barfly
Custom User Title
I'll try and explain a little better.
The tank will be up against a wall. The space between the back of the tank and the wall is about 1". Hence, no room for plumbing in the back. The overflow box will run the complete length of the back and will also run up both sides of the tank, stopping about 6 inches from the front of the tank. I would like to run all the drains on the right side of the tank. My thinking is that the box along the back and left side, don't need to be as wide or deep (no plumbing), therefore I could have the box only be about 2" wide by 3" deep. On the right side where I plan to have the plumbing, the box would be 5" wide x 5" deep. Basically a U shaped box that is wider and deeper on the side with the drains. As far as the size of the plumbing, I will us 1.5". I remembered reading where Bean had to make a modification and I was trying to avoid this if possible. I think I just confused the issue mentioning the CL. I was trying to figure out what a good flow rate would be for the sump system because I will derive most of my flow through a separate CL system and/or powerheads.
Hop that explains it better and thanks in advance for any help.
The tank will be up against a wall. The space between the back of the tank and the wall is about 1". Hence, no room for plumbing in the back. The overflow box will run the complete length of the back and will also run up both sides of the tank, stopping about 6 inches from the front of the tank. I would like to run all the drains on the right side of the tank. My thinking is that the box along the back and left side, don't need to be as wide or deep (no plumbing), therefore I could have the box only be about 2" wide by 3" deep. On the right side where I plan to have the plumbing, the box would be 5" wide x 5" deep. Basically a U shaped box that is wider and deeper on the side with the drains. As far as the size of the plumbing, I will us 1.5". I remembered reading where Bean had to make a modification and I was trying to avoid this if possible. I think I just confused the issue mentioning the CL. I was trying to figure out what a good flow rate would be for the sump system because I will derive most of my flow through a separate CL system and/or powerheads.
Hop that explains it better and thanks in advance for any help.
Just my respectful opinion here...
But I REALLY believe you are over complicating it. You do not need that much linear footage of overflow.
In fact, on my personal tank ( http://www.reefcentral.com/forums/showthread.php?t=1762906 ) you can see that even if you oly put your overflw on one end, you can still achieves a LOT of flow -and it will be silent.
I would question whether you may have planned so much overflow area that in order to move enough water to surface skim efficiently, you would need a tremendous sized pump for the system. Make sense?
T
But I REALLY believe you are over complicating it. You do not need that much linear footage of overflow.
In fact, on my personal tank ( http://www.reefcentral.com/forums/showthread.php?t=1762906 ) you can see that even if you oly put your overflw on one end, you can still achieves a LOT of flow -and it will be silent.
I would question whether you may have planned so much overflow area that in order to move enough water to surface skim efficiently, you would need a tremendous sized pump for the system. Make sense?
T
Barfly
Custom User Title
Thanks for the reply and respect your opinions. You know way more than me.
Do you really think that an 18" weir is enough on a 72" wide tank? I wasn't thinking about flow at all, I was just trying to make it the most efficient. I would agree, it would be a lot easier and more eye pleasing just having it on one side, but then again a 2" wide x 3" deep box along the top wouldn't be that bad if it made the system significantly more effective at skimming the surface, which is what I thought the point was, but then again, what do I know:lol2:.
Do you really think that an 18" weir is enough on a 72" wide tank? I wasn't thinking about flow at all, I was just trying to make it the most efficient. I would agree, it would be a lot easier and more eye pleasing just having it on one side, but then again a 2" wide x 3" deep box along the top wouldn't be that bad if it made the system significantly more effective at skimming the surface, which is what I thought the point was, but then again, what do I know:lol2:.
uncleof6
Active member
The longer the linear length of overflow, the more efficient surface skimming will be. This is irrespective of flow rate. Low, or high, the longer the "weir:" the thinner the layer of water above the weir will be, and the faster the surface "slime" will be removed from the tank.
Overflow on three sides of a tank, is a bit much. But depending on the target flow rate, along one 18" side, may not be enough. There is a minimum length needed. 18" on the end (without teeth,) will be good to 1200 gph. Granted, on a 72" tank, that is a bit small, but it will still skim the surface, but not as fast as it would were it the full length of the back. That should not really be a problem though.
Jim
Overflow on three sides of a tank, is a bit much. But depending on the target flow rate, along one 18" side, may not be enough. There is a minimum length needed. 18" on the end (without teeth,) will be good to 1200 gph. Granted, on a 72" tank, that is a bit small, but it will still skim the surface, but not as fast as it would were it the full length of the back. That should not really be a problem though.
Jim
No one in this hobby is an "expert". I have been at it for close to 30 years, and in no way do I feel superior to a beginner.
It is just the nature of a hobby that is contually humbling. When we learn the answer to one question - it create 5 more! But thank you for the compliment.
The area needed for the overflow will be partially determined by how much turnover rate you wish to go thru the sump. There are 2 schools of thought on sump flow: high flow, and low flow. Low flow sumps are usually so because the intent is to keep cheatomorpha, or other algaes, so you do not want to blast it around. As well, those sumps are often more compartmented. (Melev's Reef is a great resource for sump designs)
Some of us like large, high flow sumps, and to do the other things outside of the main sump. This works well *IF* you have room for it ( a basement that you can plumb to, or another room behind the tank) There is enough return flowfrom the sump return and the closed loop that I am not dependant on a lot of powerheads in the tank. Saves space, and less maintenance, and less plastic to look at.
So - once you settle on high or low flow sump, then you can size the pump, and the overflow length needed. That will also include sizing the plumbing, and thus the width/depth needed for teh overflow. Note - mine is 36'' in length, and I run a Reeflo Barracuda wide open @ approx. 10 feet of static head.
Sometimes more is better, but not always. Other considerations should include what sort of biotope you prefer. What types of corals, and fish will be in this display?
T
It is just the nature of a hobby that is contually humbling. When we learn the answer to one question - it create 5 more! But thank you for the compliment.
The area needed for the overflow will be partially determined by how much turnover rate you wish to go thru the sump. There are 2 schools of thought on sump flow: high flow, and low flow. Low flow sumps are usually so because the intent is to keep cheatomorpha, or other algaes, so you do not want to blast it around. As well, those sumps are often more compartmented. (Melev's Reef is a great resource for sump designs)
Some of us like large, high flow sumps, and to do the other things outside of the main sump. This works well *IF* you have room for it ( a basement that you can plumb to, or another room behind the tank) There is enough return flowfrom the sump return and the closed loop that I am not dependant on a lot of powerheads in the tank. Saves space, and less maintenance, and less plastic to look at.
So - once you settle on high or low flow sump, then you can size the pump, and the overflow length needed. That will also include sizing the plumbing, and thus the width/depth needed for teh overflow. Note - mine is 36'' in length, and I run a Reeflo Barracuda wide open @ approx. 10 feet of static head.
Sometimes more is better, but not always. Other considerations should include what sort of biotope you prefer. What types of corals, and fish will be in this display?
T
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