Another micro-bubble Q

[Mr_Quality]

I finally put salt water in the new 90g! All is well except for excessive spray in the sump and micro-bubbles being sent up to the main tank. Here’s the setup.

90g AGA Megaflow
Mag 9 w/ a SCWD (I don’t use the Mageaflow return).
20g sump (30” long) w/ 8” high baffles about 20” from left side.

The 1” Durso return used to drop straight down from the overflow at ~ 11” from the left side of the sump. I since put a couple 45 elbows on the 1” PVC pipe to drop the return closer to the left side of the sump (as far from the Mag 9 as possible).

The LFS guy says I’m trying to pump too much water into the sump where I don’t have enough length for bubbles to dissipate. He could be right. He suggests a Mag 5 instead of the Mag 9. The Mag 5 should feed the Magaflow return and the Mag 9 could be in a closed loop w/ the SCWD. I’ve throttled back the Mag 9 and obviously the microbubbles got better.

Does this sound like a reasonable approach? Anybody have any cool tricks to cut down on microbubbles?

Mike

[NAGA]

I would do the downsized pump at first to see. Hopefully you have the pump hooked up so that it is removed easily. I like the slow rollover approach. I have taken that to an extreme perhaps on the 750g. I have a Eheim 1060 for my circ. pump http://www.cmas-md.org/iB_html/non-cgi/emoticons/oh.gif http://www.cmas-md.org/iB_html/non-cgi/emoticons/oh.gif On the other hand I do have 6 Tunze's and I don't have any bubble issues.

Jeff

[Mr_Quality]

Thanks Jeff,

I replaced the Mag 9 w/ a Mag 5 and sent the water back to the tank using the standard AGA overflow return. Gosh that 5 seams whimpy.:glare:

Now I really need to set up that closed loop w/ the SCWD and Mag 9 to get the amount of water movement I want.

So far so good,
Mike

[AquariaUSA]

The length of the sump would have to be probably about 6' long if you wanted them to dissapate from 900 gph http://www.cmas-md.org/iB_html/non-cgi/emoticons/smile.gif The water entry into the sump and the flowthru is what limits the amount of bubbles that get returned to the main tank (unless you have some sort of venturi action going on). I have 3 Mag12s and I think a QuietOne 3/4000 running on the OCE 200 straight (keep meaning to set up some closed loop seaswirls! Unless the sump level gets within 1" of the pumps I have little bubble return. But my sump is a 125 with baffles, Japanese filter material, etc.

Do you have two baffles in the sump or one?...add some of the Japanese filter material (made for ponds, sold off the roll 18" wide polymaterial) prior to pump return. Divert the drain from the overflow into a small 16oz deli cup or something if you have too much agitation in that little sump. I would use the 900 if you plan mostly SPS or load the tank with powerheads and use the 500. But the closed loop idea will also work.

[Mr_Quality]

I installed the closed loop and it’s been running overnight. Now the closed loop is spewing micro-bubbles (I can’t win). I don’t find any leaks where water is getting out, so I don’t think air is getting in. The design is much live Melev’s here (http://www.sparklingfloorservice.com/tank/closedloop.html), except I use a Mag 9, my pump sits on the floor so the flow distances are longer, and I use 1” PVC from the tank to the pump and ¾” back to the tank. I know that there is air trapped at the top of the system. I don’t see anyway around this. I suspect I’m pulling that trapped air down into the pump, chopping it up, and sending it into the tank. But I figured that eventually that air would get expelled, consimed, and the bubbles would go away, but after running all night – still have micro-bubbles. I can get bubble-free if I close the return valve a little and throttle back the flow, but I want to use all of the pump I paid for. Argh http://www.cmas-md.org/iB_html/non-cgi/emoticons/duelies.gif

Any ideas from the squad would be appreciated!!!!!

[Mr_Quality]

I just found this (http://www.reefcentral.com/forums/showthread.php?s=&threadid=335076&highlight=closed+loop+bubbles) link on RC. Maybe I'll replace the 5 ft length of 1" PVC (from tank to pump) w/ 1 1/2" or even 2".   http://www.cmas-md.org/iB_html/non-cgi/emoticons/tounge.gif

Mike

[Mr_Quality]

PROBLEM SOLVED! http://www.cmas-md.org/iB_html/non-cgi/emoticons/biggrin.gif  http://www.cmas-md.org/iB_html/non-cgi/emoticons/biggrin.gif

I was smart enough to put a drain valve at the bottom to allow me to easily drain the loop for servicing. I have a T-fitting w/ a cap at the top to allow priming of the system. Both of those had small pockets where air was trapped. Last night I put a spped-fit air-bleed valve at the top. I drained just a bit out the bottom, just 'till I expelled any trapped air down there. Then I sucked all the trapped air from the top. Fired it up...No Bubbles!!! http://www.cmas-md.org/iB_html/non-cgi/emoticons/biggrin.gif  http://www.cmas-md.org/iB_html/non-cgi/emoticons/wink.gif  http://www.cmas-md.org/iB_html/non-cgi/emoticons/biggrin.gif

Thanks for your help,
Mike

[dgasmd]

Hey, that's why they call you Mr_Quality http://www.cmas-md.org/iB_html/non-cgi/emoticons/wink.gif http://www.cmas-md.org/iB_html/non-cgi/emoticons/biggrin.gif http://www.cmas-md.org/iB_html/non-cgi/emoticons/biggrin.gif http://www.cmas-md.org/iB_html/non-cgi/emoticons/biggrin.gif

[sparkey65]

i also have a problem with micro bubbles returning into my tank from my sump since i put my skimmer in my sump i only have a divider betwwen my overflow from the tank and my return i have a mag 1200gph if i add some baffles will this help?

[sparkey65]

if i turn the skimmer off the micro bubbles do go away

[Mike & Tori]

Sounds like the baffles would help you. Or put a sponge where your skimmer returns into the sump.