Microbubble mystery...

I set up a 90 a little over 2 months ago and since have had a micro bubble problem in the DT. I talked to tangster and thought it was maybe the mag 7 cavating, since ive found out it isnt cause its still doing it after the putting an elbow on the inlet. I tried a sponge in the first over baffle...nothing. Ive noticed there are short bursts of micro bubbles coming from the return loclines. It like a 1 second burst from both outlets and about 200 or so micobubbles from each outlet. I have the standard all glass plumbing kit, cut it to the specific length they state and screwed the locline fitting onto the elbow they provided. Where could short bursts of micro bubbles be coming from if its just not steady microbubbles making it over the baffle system? There doesnt even appear to be that many micros floating around in the return part of my sump to make it to the mag to be returned to the DT. Im at a lose for an explanation anymore....could the locline crap suck air? I cant think of anything anymore. Ive turned power heads off for a nite and still bubbles....cut skimmer off....still bubbles just slightly decreased amount....drain for tank is emptied into filter sock so micros from that is very minimal. Any ideas???

 

hows the water level in the part of the sump where the pump is? is it a couple of inches over the inlet of the pump?

 

yeah...about 5 inches or so...i even layed on the floor and watched to see if there was anything building up or looking weird by the inlet. Looks the same all the time.

 

you noticing any salt buildup on the pipes anywhere? that could indicate a small pinhole leak somewhere that is allowing air in... other than that I'd have to see it to have more ideas tang is usually really thorough I'm sure he'll come up with more ideas

 

no salt build up other than just the salt creep...

 

are the returns themselves vortexing? i recently redid my return system - the return outputs are a little close (about 1.25 inch) to the surface of the water. about every 10 minutes or so, one of them with create a vortex, it will slowly grow to reach the outflow, and the blow a blast of microbubbles as it disrupts. back to the workbench....

 

1 outlet is an inch below water level and the other is around 4 inches or so. I dont see like a funnel sucking air above either one. The burst of bubbles is about every 2 or 3 mins....some of the Locline i above water level...whos isnt tho? Could that be a factor?

 

Is your skimmer's outlet pouring on top off your return pump? If no, then theres something feeding those micro-bubbles and its your return pump thats pumping it up to your DT. Or its the locline that is too close to the surface as mentioned below. That was happening to me too, I just lowered the loc-line. Look carefully. Luna

 

i had the same trouble after i upgraded my light system.....fine bubbles were coming up from the substrate. My tank has been set up for years and never had that happen but it went away after 2 months.....have no clue but thats what it was from

 

Gas exchange, thats normal. You must have a DSB huh? Luna