Running out of solutions for microbubble problem

I've been hunting down a solution to my microbubble problem and I thought I had it solved. My skimmer and drain outlet in my sump puts in quite a few microbubbles. I solved this by putting in a large piece of white filter pad in one of the baffles. My return section with my Eheim pump has no visible microbubbles--yet, there they are swirling around my tank. I just replaced the majority of my return flex tubing (5/8 inch) with no change. The funny part is the bubbles seem to come from the right side of the tank where my Koralia 750 is. Anyone have any ideas what to do?

 

Three potential sources I can think of: the overflow, the skimmer, or possibly the return pump.

Usually though, it's due to there being too much flow through the sump and/or insufficient baffling between the skimmer and the return pump.

So, if you would, please share/discribe the set-up of your sump, including skimmer location, return pump location, # of baffles and spacing, return pump size (amount of flow), and the approximate size of your sump.

 

My sump is a 29g with the typical 3 sections (skimmer, return, fuge). I have a 3-baffle system (1.25 inches between). I know the skimmer is putting a bunch of bubbles out and the drain from the DT does too. These are all stopped by the white filter pad in the first baffle--there are no bubbles in the second baffle or return section.

I'm wondering if dialing down the return pump (Eheim 1260) with a ball valve could cause the bubbles? When I had my 1250 I ran it wide open with no bubbles, but of course the flow was much slower.

 

The pump is run submerged im guessing?

 

The filter pad will help with bubble, but it might not be getting them all even if it looks like it.

The ball valve shouldn't create bubbles, unless it was leaking somehow.

If you dial back the flow more, do the bubbles stop? If so, they're coming from your skimmer and moving too quickly through the baffles to all pop before they get to the return pump.

 

Yes, pump is submerged.

 

Dialing back a bit more helps, but doesn't alleviate the problem. I have a couple filter socks on order and may try one in the return area and/or drain outlet and see what happens.

 

is your tank drilled, or are using an overflow? and if so what kind?

 

My tank has one hole drilled with an internal overflow box. It has a T-junction right after the overflow with a cap and tiny hole in it.

 

Lower the Koralia further in the tank. I found with some of my powerheads they were vortexing and creating bubbles. It was easier to see at night with a flashlight than during the day.