Microbubbles going THROUGH my filter sock! This sucks

[Gooli]

I'm pretty annoyed now because i got a 100 micron filter sock from Marine Depot to eliminate microbubbles and the 600gph drain into the sock breaks up the air into tiny bubbles which travel through 2 bubble traps, and live rock rubble to the return pump, Mag 9.5.

These little microbubbles are really a pain - i think i'm gonna slow down the drain with a Mag 7 return pump or a eheim 1250 to get around 300-400gph.

any comments? (i know about the bubble tower - will work on that too)

thanks for the input

 

[slinger]

Is this new plumbing? If so, give it a few weeks for the pumps to slime over, which will reduce the turbulence and surface resistance to the flowing water and should reduce your microbubble problem by a fair amount.

With regards to the bubble tower, I made one out of 3" PVC with holes drilled in the side of the bottom endcap, and the velocity of the water draining into bubble tower was enough to drive the microbubbles through the rock rubble in the tube and out the holes in the bottom. Obviously this renders the bubble tower useless. I'm starting to think they only work for very low flow overflows (way less than 600GPH)...

 

[Gooli]

plumbing is a year old...i have come to the same conclusion...gotta slow the drain and do a closed loop

 

[slinger]

Actually I did have one other thought. Are you absolutely sure the microbubbles you're seeing originate from the drain into the sump? The reason I ask is that it's possible the microbubbles entering the main tank could be produced as a result of a venturi effect somewhere in the return line. I had this problem in my return line due to unsubmerged locline plumbing, and possibly because of a partially submerged siphon break hole. Others have reported problems due to bulkheads, unions, and plumbing seals not being fully airtight. Anyway, just a thought...

 

[Gooli]

i hear ya...but my return is using flexible hose with a submerged pump and is well connected to a seaswirl - no way is air getting in. there is no syphon hole either

 

[slinger]

Well, crap! I'm running out of ideas...

I guess the key things here are slowing down the velocity of water going through the sump, and possibly slowing the velocity of water entering the sump through the drain. I have a 90G with a 30G sump just as you do, and I was originally going to use a Mag 7 as a return, but it was too loud, too hot, and suffered with my 3/4" diameter return piping and head pressure. I switched to an eheim 1260 and am totally glad I did - it's quiet, efficient, and handles head pressure and smaller piping easily.

I tee off the return from the 1260 to feed a small refugioum compartment, so I'd guess I return about 300-400 GPH back to the tank, which I think is plenty, but then I'm not driving a Sea-swirl either.

 

[Gooli]

cool..we have a similar setup.
i think i'm gonna go with the 1250 eheim.