Horizontal Overflow Questions

[Randall_James]

<a href=showthread.php?s=&postid=10067929#post10067929 target=_blank>Originally posted</a> by BeanAnimal
Easily solved by placing the overflow lip at the bottom edge of the trim

I can see for HOB types, but for something that is being DIYed and will be attached to the aquarium, just attach it where it shuld go and no worries.

not if the flow is too high through the unit. The water level at 3X is going to be a lot different from 5-8X You need to take a look at many of the commercial overflows, they have this adjustable gate..

I have setup a number of custom tanks that this gate adjustment was needed to tune the water level. If they lip was at the plastic trim level, the tank would have overflowed.... But then again, maybe these tanks were setup all wrong...

 

[BeanAnimal]

Or the overflows were too narrow

 

[BeanAnimal]

Lets put this another way... of the thickness of the water going over the weir is thicker than the trim of the tank, then the weir needs to be wider, as the surface skimming is suffering.

 

[Randall_James]

Well I will call Oceanic and tell them that they are screwed up then... Sure seems like they would have known what there were doing. Cant find good products anywhere I guess...

 

[BeanAnimal]

Randall, there is no need to be flip about it.

But now that you mention it... just because a manufacturer does something does not mean that they "know what they are doing".

Look at how narrow the built in overflows are, not to mention that they have teeth. Many of the large "reef ready" tanks only have a few linear inches of overflow. Jut because they sell it and sell a lot of it, does not mean it is well designed. We could go through dozens of examples.

Using that logic you responded with, why "mod" anything? Afterall, the manufacturers "knew what they were doing" why second guess them?

The point is that if you are going to go through the effort of DIYing something, why mimic the flaws of an off the shelf design? Why not maximize the potential of your project by using critical thinking and logic.

 

[Randall_James]

Then why limit the ability to tune the water level in the display? If you feel that this adjustment ability is a "Flaw" then dont use it

the post was "tongue in cheek" and you simply highlighted my point..

Having set up custom display tanks for a number of years, I can attest to the fact that being able to adjust the display water level can be a real asset..

Just the "left to right" adjustment can be of help as to maximize the skimming ability of the overflow as very few tanks are "perfectly level" For the few minutes it takes to have the gate, i will stick with them

Buy hey, everyone has their own way of doing things and your avatar can beat up my avatar :lol:

Cheers...

 

[BeanAnimal]

<a href=showthread.php?s=&postid=10068513#post10068513 target=_blank>Originally posted</a> by Randall_James
Then why limit the ability to tune the water level in the display? If you feel that this adjustment ability is a "Flaw" then dont use it

You lost me there... I think your thinking about this too deeply.

WHY would you go through the trouble to make a weir with an adjustable height, when it is not AT ALL needed?

THE POINT WAS that if you design YOUR OWN OVERFLOW in such a way that it is narrow enough to cause the tank to overflow the trim, THEN THE OVERFLOW WEIR IS SEVERELY TOO NARROW AND YOU HAVE DEFEATED THE PURPOSE OF DIY.

Just becuase the DESIGN of the manufacturers overflow is "flawed" (I.E. too narrow) does not mean that we should mimic this in our own designs and then compensate by adding an adjustable gate. It makes utterly zero sense.

the post was "tongue in cheek" and you simply highlighted my point..

I don't think you got the point

Having set up custom display tanks for a number of years, I can attest to the fact that being able to adjust the display water level can be a real asset..

Only if you built the overflow too narrow for the desired flow. That is surface skimming 101. Check the calculator on the RC homepage and run some examples.

Let me say this again in simple terms. If the water going over the overflow is 2" deep then you are pushing WAY too much water over it.

Just the "left to right" adjustment can be of help as to maximize the skimming ability of the overflow as very few tanks are "perfectly level" For the few minutes it takes to have the gate, i will stick with them

Randall, if the water is going over thick enough to need HEIGHT adjusted for the trim, then the water is thick enough to NOT make a difference RIGHT TO LEFT even if the tank were off by 1" over 4'.

Lets break this down even further. For the water to be thin enough to be affected by RIGHT TO LEFT trueness, then the overflow, even at 20X flow would need to be so wide that adjustment would not be needed if it were placed at the trim line.

BUT back to the whole DIY aspect. If you are going to DIY an overflow, then you would level it in the tank. You would also take the time to properly level the tank if you moved it, and this level the overflow.

You are totaly free to do what you like, I am not trying to stop you. I am however trying to give the OP some perspective on the subject. Going through the trouble of building a sliding gate is certainly not needed if the overflows function as it pertains to surface skimming is considered.

Buy hey, everyone has their own way of doing things and your avatar can beat up my avatar :lol:

Cheers...

Yup but sometimes upon closer examination we do things that are simply not needed nor gain us any benefit, especialy for the trouble involved. Like I said, I am not trying to change your ways. I am however trying to illustrate the facts to the others who are reading along.

The major point being that surface skimming is very important and a narrow overflow is not a good idea if it can be avoided.

 

[Randall_James]

Bean you need to take a solid stance on this thing, in the other thread that you started this little spat about you advocated running 20X to 50X flow through the overflow (the 120G tank remember?).

Now you are back to "no slots, it dilutes the skimmed water" So is the sky blue or isn't it? If I say yes, you will say no?

You started this one out without even really reading the thread first before starting the debate....

 

[BeanAnimal]

What are you talking about Randall?

I did not "advocate" 50X flow through the overlflow. I mentioned OPTIONS regarding the setup of an overflow.

I ALSO SAID that I tend to PREFER "higher flow sumps" as part of my methodology.

To be 100% clear:
I prefer VERY LARGE "SUMPS" with LR that are as big, or bigger than the display. They need a significant flow to do their job. I prefer that the bulk of the equipment be connected to the sump as well. Though there is SOME loss of flow with a larger return pump, it is not that much worse than a closed loop. I do not like powerheads, streams or other "wave makers" in the tank, they are UGLY and out of place, esp in smaller systems where they can not be hidden.

But now that you ask... a 6' long 120 gallon tank with a coast to coast overflow would easily handle 50x flow without going over the trim. EASILY. No need for anadjustable gate and it would still have much better surface skimming than almost any tank with a little square overflow box.

So I am clear:
It would not be IDEAL with regard to surface skimming but would be manageble if there were not enough bulkheads to plumb the closed loop intakes (part of the point in the other thread).

SO no Randall... I have taken a solid stance You have just taken thoughts fully out of context.

Now you are back to "no slots, it dilutes the skimmed water" So is the sky blue or isn't it? If I say yes, you will say no?

Heh? I am not "back to anything". NO MATTER WHAT THE FLOW RATE, why put teeth into to further reduce the surface skimming? Once again, your not looking at this from the big picture. The SLOTS or NO SLOTS arguement has nothing to do with the turnover... no slots provides better surface skimming in any flow situation.

Your really twisting here randall... This is getting silly.

You started this one out without even really reading the thread first before starting the debate....

What does that have to do with anything? We are, well where we are.

I could have said "basketball is a stupid sport" and if you responded, then the conversation would be ABOUT what I said, not the parent topic.

This is ABOUT what I said and your reasoning as to why I would be wrong, and now about my "solid stance". In either case, I don't think you understand.

That is certainly fine... lets just move on to the next thread. I honestly don't want to fight about something so silly.

Enjoy.

 

[mr.wilson]

Commercial systems don't use a horizontal overflow. Proper flow patterns (toward the overflow) and turnover rates (3x/hr) will skim a very thin layer of surfactant film from the surface.

If you have 50x/hr flow rates going over the overflow, by all you means, use a coast to coast overflow with as many drains and emergency overflows as you can fit.

 

[psyco_guy_abd]

This is getting a little out of hand, can't we just all state our idea's and let the OP figure out what he wants to do with them?

FWIW NeveSSL I didn't use teeth, I agree with Bean that they reduce the total area of your overflow. Think about it like this if you have 10" of overflow and then add 20 .25" teeth then you really only have 5" of overflow because water can't go through the teeth. I also didn't use an adjustable gate. I just cut my overflow level with the tank trim and my water line is right at or just above the tank trim depending on if my return pump is clean or not. I didn't think I would ever need to adjust the water level, and so far I haven't ever wanted to. One advantage to the adjustable plate is that you could remove it for cleaning, might be easier then trying to scrub in tank..

 

[Randall_James]

<a href=showthread.php?s=&postid=10075608#post10075608 target=_blank>Originally posted</a> by psyco_guy_abd
This is getting a little out of hand, can't we just all state our idea's and let the OP figure out what he wants to do with them?

FWIW NeveSSL I didn't use teeth, I agree with Bean that they reduce the total area of your overflow. Think about it like this if you have 10" of overflow and then add 20 .25" teeth then you really only have 5" of overflow because water can't go through the teeth. I also didn't use an adjustable gate. I just cut my overflow level with the tank trim and my water line is right at or just above the tank trim depending on if my return pump is clean or not. I didn't think I would ever need to adjust the water level, and so far I haven't ever wanted to. One advantage to the adjustable plate is that you could remove it for cleaning, might be easier then trying to scrub in tank..

There were NEVER any teeth in this equation to start with, that was were Bean stepped in and commented on them and got the whole thread sort of sidetracked....

 

[BeanAnimal]

Randall....

Honestly, get past it. The focus quickly turned to the other topics and were covered in depth. It is all in context and all fairly straight forward.

 

[tropicalfishguy]

Don't bother Randall, its not even worth it dude. Like talking
to a brick wall

 

[NeveSSL]

<a href=showthread.php?s=&postid=10075608#post10075608 target=_blank>Originally posted</a> by psyco_guy_abd
This is getting a little out of hand, can't we just all state our idea's and let the OP figure out what he wants to do with them?

FWIW NeveSSL I didn't use teeth, I agree with Bean that they reduce the total area of your overflow. Think about it like this if you have 10" of overflow and then add 20 .25" teeth then you really only have 5" of overflow because water can't go through the teeth. I also didn't use an adjustable gate. I just cut my overflow level with the tank trim and my water line is right at or just above the tank trim depending on if my return pump is clean or not. I didn't think I would ever need to adjust the water level, and so far I haven't ever wanted to. One advantage to the adjustable plate is that you could remove it for cleaning, might be easier then trying to scrub in tank..

Cool deal, man. I think I will just do it at the top of the trim. I just want it to look good and a gate makes sense, but I think I may just run a bead of silicone over it if its still too low. I've got a feeling my return rate will be high enough, though, that it will be over.

I pick up my glass tomorrow! I'm excited... but I'm nervous about drilling 4 holes! :eek2:

Thanks!

Brandon

 

[tropicalfishguy]

How are you drilling the holes? Dremel or coring bit? I have drilled many tanks, never broke one(knock on wood) still get a little nervous, especially when its not mine. Just remember nice and slow, lots of water. Good luck with the drilling

 

[NeveSSL]

I'll be using a diamond hole saw, which will hopefully make it a bit easier.

I'm planning on following the guide in the DIY forum (can't remember who did it right off), so I'll just take my time and I should be ok.

Brandon

 

[BeanAnimal]

<a href=showthread.php?s=&postid=10078824#post10078824 target=_blank>Originally posted</a> by tropicalfishguy
Don't bother Randall, its not even worth it dude. Like talking
to a brick wall

Nice personal attack... get a clue and learn to follow the conext of a thread. Maybe comment on the substance next time instead of slinging insults.

Better yet, please tell me where I am wrong here?

 

[Randall_James]

You came on the thread, made a comment about something that was not even an issue (because you did not read the thread)and have continued the great escape ever since.... just let it go.. Get a clue and learn to follow the context of the thread..

 

[BeanAnimal]

NeveSSL

There is abosuletly ZERO reason to put an adjustable gate on an overflow that is as wide as you are talking about.

Just place top edge of the overflow at the bottom edge of the trim. If the overflow was only 24" long, you would have to put 10,000 GPH over it to get a lip of water thick enough to overflow the tank.

Also, as mentioned (3) bulkheads will handle all of the flow, though adding a 4th while you are doing the work will be fine, you never know what you may want it for.

The standpipe setup that I mentioned is fullproof and dead silent. It does not need adjustment and is a LOT less trouble and more reliable than a durso or stockman standpipe setup. It is not a gimmic, just a simple application of logic and used in wastewater treatment and other applications.