Bubble Trap Baffles

[HJ99]

I'm doing a DIY sump. I've read the pros and cons of over under over vrs under over under. I have also seen a few with just two baffles that are over and under. Are three baffles really needed ? Eliminating one would help with a space issue I'm having.

 

[Gtinnel]

I used over-under-over for my sump and if I'm being honest I never understood why the last over is needed. I understand the first over is to set the water level, and the under is so that the bubbles hopefully won't travel down and into the next chamber, but I've never understood the benefit of the third baffle.
If possible why not install 2 and then run some water through it, then if bubbles are an issue install the third one?

 

[HJ99]

Good idea. I actually have three glued in with under over under. I'd like to cut the first one out to make room for a filter roller. Then it would just be over and under.

 

[Gtinnel]

Good idea. I actually have three glued in with under over under. I'd like to cut the first one out to make room for a filter roller. Then it would just be over and under.

If it works well with bubbles not getting into the next chamber let us know. I wouldn't mind getting an extra inch or two of usable space in my sump.

 

[HJ99]

If it works well with bubbles not getting into the next chamber let us know. I wouldn't mind getting an extra inch or two of usable space in my sump.

Will do. It may be a while since we are still waiting on the DT. I've been keeping busy working on this stuff in the meantime.

 

[ajjw0828]

With my DIY sump I just did two baffles. I liked it for space reasons, and had enough room in my return section to not have my pump tight against the second baffle. However I've since Added a 210 gallon to the system and had to add additional pump. The face of the pump is close to that second baffle now so some bubbles reach the under portion of the second baffle and get sucked into my pump and show as micro bubbles in my display. For this reason I now wish I had that third baffle installed. I never noticed an issue though when my first pump was a couple inches away from the second baffle. I try and reduce the fall of water by keeping my ATO level similar to the main portion of the sump but bubbles still make it.

 

[fade2black]

I think a lot depends on the flow rate through the baffles too. If they are close together or you have significant flow through your sump, it will not allow the bubbles time to rise.

 

[HJ99]

I think a lot depends on the flow rate through the baffles too. If they are close together or you have significant flow through your sump, it will not allow the bubbles time to rise.

I had also thought about this. I have 1 1/4" space for the under baffle and it's 17.5 wide. The space between is 2 " . The level will be dropping from 18" to about 15" Pump is rated at 1500gph but guessing flow around 900 gph considering head pressure and splitting off the return for the refugium.

 

[HJ99]

With my DIY sump I just did two baffles. I liked it for space reasons, and had enough room in my return section to not have my pump tight against the second baffle. However I've since Added a 210 gallon to the system and had to add additional pump. The face of the pump is close to that second baffle now so some bubbles reach the under portion of the second baffle and get sucked into my pump and show as micro bubbles in my display. For this reason I now wish I had that third baffle installed. I never noticed an issue though when my first pump was a couple inches away from the second baffle. I try and reduce the fall of water by keeping my ATO level similar to the main portion of the sump but bubbles still make it.

I'm using an external pump. The return is drilled with an outlet that's about a foot away from the baffle so it may be OK.

 

[RocketEngineer]

My view on the third baffle is its a good idea but not required. The reason for it is momentum so that any bubble that gets pushed under the second baffle is now shoved upward with the flow vs against the flow, thus making it more likely to contact the surface and pop. But, if you need the room, it can be left out.

 

[threebuoys]

I've had good luck using only two baffles (over/under) and placing a few plastic kitchen scrubbing pads between the two to slow the air bubbles down before they go under. Not enough to slow the water down, just enough to cause the larger air bubbles to reverse course so to speak. The two baffles are only 1 1/4" apart. Maybe if they were further apart I would not have the problem, but my solution seems to suffice for my situation.

 

[Gtinnel]

I've had good luck using only two baffles (over/under) and placing a few plastic kitchen scrubbing pads between the two to slow the air bubbles down before they go under. Not enough to slow the water down, just enough to cause the larger air bubbles to reverse course so to speak. The two baffles are only 1 1/4" apart. Maybe if they were further apart I would not have the problem, but my solution seems to suffice for my situation.

On my sump I used to put filter pads in between the baffles, not to catch bubbles but to actually work as a filter because I don't have room for filter socks. If anyone uses this method they have to make sure to keep the pads clean otherwise their water level will fluctuate. I got tired of my skimmer acting up so I quit using them.