Ideal baffle design

[R33f3r]

I have a 20G high sump and I want to implement a 3 baffle system to rid the tank of microbubbles. How far do the baffles need to be apart from one another? I won't use the sump for any refugium, just my skimmer and return pump. Thank you.

[Acrylics]

Originally posted by R33f3r
I have a 20G high sump and I want to implement a 3 baffle system to rid the tank of microbubbles. How far do the baffles need to be apart from one another? I won't use the sump for any refugium, just my skimmer and return pump. Thank you.

They don't *need* to be any particular distance but most folks use about 2" between them.

HTH,
James

[Zander]

how high should they be from the bottom of the tank?

[Chris_Reef]

From what I understand it depends on how much you have flowing through the sump. Faster water flow means more space needed to rid the bubbles.

But take anything I say with a grain of salt as I have no practical experience yet.

[Entropy]

I put my baffles an inch apart and it is not enough (800 gallons per hour). The flow is so strong that it pushes the bubbles right through. Back to the drawing board for me :)

[Acrylics]

Originally posted by sdgtivr6
how high should they be from the bottom of the tank?

As others have stated, it depends on flow.
But most folks hav the risers (glued to the bottom) go up 6-8" from the bottom and the gap on the other baffle(s) about 2" from the bottom.

[charley75]

Are the bubbles coming from the drain line? Is your sump drilled or not? If they are coming from the drain line and your sump is not drilled there is an easier way to eliminate the bubbles. I learned this from Ken Stockman......What I did was get a 3 or 4 inch diameter piece of PVC and a matching flat cap. Cut the piece of PVC so that it is an inch or so taller than the water level in your sump. Then you put that in your sump standing up and insert your drain line so it reaches an inch or 2 from the bottom. That's pretty much it...EZ cheap bubble trap.
Charley

[Sealily]

I'll just bet that works nice for sump-protein skimmers, too, especially to cut down on the ever-falling water-fall noise levels. I like it!

[Spudds]

quote:
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Originally posted by charley75
What I did was get a 3 or 4 inch diameter piece of PVC and a matching flat cap. Cut the piece of PVC so that it is an inch or so taller than the water level in your sump. Then you put that in your sump standing up and insert your drain line so it reaches an inch or 2 from the bottom.
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Where does the drain water exit this setup? Is there a hole at the bottom of the 3in diameter PVC tube where the water exits? Maybe I just don't know what a flat cap is, but i don't understand where the drain water leaves this bubble trap. Do you drill a hole in the bottom?

Spudds.

[charley75]

The water exits the top.... the top is open. Just picture putting a tall drinking glass (taller than the depth of water) in your sump and sticking your drain line in it. The water is forced to exit the top(the bubbles exit the surface here), and then the water falls and inch or so to the surface of your water in the sump. The only problem I had with this is a concentrated area of salt spray.
Charley

[Spudds]

Ah ok, I thought the idea was for the water to go out the bottom and hope the bubbles went to the top. I see now thought, it's basically just an extra overflow.

Spudds.

[webpolk]

charley75, is this method quiet enough still?

Sounds very interesting, less space for baffles and less acrylic to buy when I build.

Steve

[H20ENG]

I always run my baffles longitudinally back and forth, rather than over / under. This gives the water a much greater detention time through the baffles and allows even the tiniest bubbles to escape.
Also, you dont limit your pump intake chamber to just one little pocket of water on the side of your sump.
HTH,
Chris

[Spudds]

I tried Charley75's idea and it cut down a ton on the bubbles that were making it to the first baffle. So much so that I could take out the sponge I had put inbetween the baffles. The limiting factor has not changed though, now the problem is that if the flow is too high, air will bubble up quickly and water will splash out and spray all over the place. So basically an idea is needed to increase the flow rate one of these can handle.

I believe the important factor here is the surface area of the pipe. So increasing the radius of the pipe is one clear way to go. Doubling your radius would allow you to handle 4 times as much water in a non-turbulent sort of way. Or maybe that's irrelevant and at high flow rates you will get that bubbling effect no matter what.

Another idea I had was to drill small holes in the bottom of the pipe, you could even put mesh over them if you are worried about bubbles. This might help the pipe handle more GPH.

Spudds.

[charley75]

I finally just put a lid on mine to keep the inside of the stand from getting soaked.
Charley

[fade2black]

Originally posted by H20ENG
I always run my baffles longitudinally back and forth, rather than over / under. This gives the water a much greater detention time through the baffles and allows even the tiniest bubbles to escape.
Also, you dont limit your pump intake chamber to just one little pocket of water on the side of your sump.
HTH,
Chris

That is a great idea! That is definitely going in my sump plans!!

Fade

[H20ENG]

I've used it quite a bit. As also mentioned, a cover over this area will help contain any salt creep from bubbles.
My new sump drawing has the longitudinal baffles in the back, and the refugium up front so you can sit on the floor and watch it for hours like a dork.:D

[guitarfish]

H20ENG - any chance you can post a pic of you logitudinal sump baffle design? I'm struggling with a microbubble issue.

[thedogofwar]

IMO the bigegst flaw I see in baffle design is the last baffle. Every1 I see has the last baffle as an over type.

I designed my 10G fuge with the baffles 2" apart, the last baffle forces the water underneath of it. The previous baffle creates bubbles from a 2" fall. Under my original design, those bubbles are subjected to the wrath of the return pump. Now, they never get under the last baffle.

Besides a pump restart, my microbubble ploblem is eliminated.

I've never thought about it but the horizontal baffles sounds like a great idea. I have only one concern. For those that rely on pump return area volume to regulate the chance of display overflow. Like me, My pump will burn up b4 my tank spills on my hardwood floors.

[werew]

I'm glad this thread came up. I'm building a tall 120 gal. tank and in the future would like +800 gph flow rate thru the sump. To start off with, i'm going to try 600-700'ish.

I suppose that spacing the bubble trap's baffles too far apart (to an extent) won't hurt whereas too close together and you get flow restriction.

I've seen many sumps with these baffles placed 1" apart and 1" from the bottom of sump... I guess i'll go with 1 3/4" apart and 1 1/2" from the bottom, just to be safe.

My baffles will be about 9" - 10" at the tallest.

Dimensions are 30"wide x 18"tall x 17"deep. The main flow will go under a refugium that will be in the center, and I guess i'd better make the clearance 2".

I made a rough drawing and put it in my gallery if anyone cares to comment on it.... constructive criticism is appreciated.

Paul

[jdieck]

About two inches from the bottom and two to two and a half between two of them and then about 5 to 6 inches between the third. This additional space will allow you to have enough space to place chemical media bag directly on the flow (Carbon, Phosphate adsorvant etc.)

[gbtower]

Longitudinal baffles would seem ideal, but doesn't it take up a lot more space in the sump to make sure the channels are wide enough to keep the flow slow enough? Or is water velocity less important than distance traveled in this case?

[jdieck]

Longitudinal baffles will allow microbubbles to rise to the surface by themselves and may increase the overall water velocity which in turn may carry the bubbles into your pump's suction. Trnsversal baffles will force the bubbles to the surface creating what IMO will be faster action to get rid of them. Besides I think longitudinal will be more difficult to arrange in a sump where you may want to have your skimmer and some media bags included.

Notice that longitudinal baffles may be very useful to increase time when as for example you want to use filter feeders to clean the water (Instead of arefugium) and why not they may also be effective in a refugium design to allow more time for the macro to work out it's magic and the available water.

[H20ENG]

Good points above.
I use a float switch in the sump and in the tank to avoid flooding OR burning up the pump.
The over under baffles usually remove the bubbles, however, if the sump is not full enough, or velocities too high, they only add bubbles in the end.
The longitudinal baffles create the maximum contact time. Even with fairly high velocities, there is still enough time for the bubbles to disperse.
This concept is used in everything from chlorine contact basins at water treatment plants to the "raceways" at hatcheries.
To each his own, just putting it out there.
Chris

[tat2shawn]

Hi.
Does anyone have a pic of what these longitudinal baffles look like?
Thanks
tat2shawn

[H20ENG]

Like this. Top view of sump.
Baffles are longitudinal, so the water does not travel over / under as in horizontal baffle designs.

[mikeo1210]

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