Sump, microbubbles, lots of questions

Okay, I have a "sealife" wetdry that I am using as a sump. I've got the bioballs floating in the water for more bacteria population and about 10 pounds of rubble rock in there. I'm running a 3/4 inch version of the "Covey" PVC overflow which I have to adjust so water exits into the sump below (or closer to) the water line. I'm running the water into the big side of sump, and my pump (12V marine bilge pump, working great so far 300 gph measured for head) is suction cupped in the diagonal section under where bio balls "should" be in a wet dry. The only issue i've got besides the noise from the waterfall which I'll be fixing with a bit more PVC work, is the fact that because I have no baffles I have tons of microbubbles. Nothing in the tank seems to care but I do

Looking on the return side to fix the problem i checked my "siphon break" but its shooting a solid stream of water out so I dont think there is any "input" of air there. Also, I cant see a stream of microbubbles, they are just swirling in the tank.

The pump has no vortex, as it picks up from the bottom of the pump (one reason I chose a bilge pump, which I checked and made sure it was okay, plastic and ceramic are the only parts exposed to water).

This said, the only place I think I could be getting bubbles would be from the froth of the water falling into the sump.

Does anyone think I could get the "foam block" piece that would be in a wet/dry and install that, would that help solve the bubbles. I can't take it out and install baffles (I should have done this before, but its under my tank which only has an 8" wide door and the sump is 8" wide itself

Any other advice would be great, and can someone tell me should I have rubble rock up to the water line, or is about 3/4 the way okay?

Thanks a bunch

 

For my microbubble problem, I inserted a splash box at the inlet to my sump. Mine is a arcylic spagetti container with multiple holes drilled in the bottom and first few inches of the bottom sides filled with LR rubble. Most of the air bubbles dissapate in the splash box. The water goes out the drilled holes into the sump. Microbubbles immediately disappeared.

Don't know if that can work in your set up, but it solved my bubble issue easily.

Hope that helped.

Mark