Microbubbles from Return Plumbing Mystery

theKoolAidMan · Dec 15, 2018

Ever since I get up this Reefer Nano I've been getting a small quantity of miro bubbles coming out of the return nozzle in the tank. It would come and go in spurts and was a small quantity but always kept some bubbles being blown around the tank, which just annoyed me.

Today I cleaned the return pump (an AI Mightyjet DC pump), changed the return host, and reassembled the return nozzle assembly. These bubbles are not present in the sump and not coming from a skimmer (the only equipment in the sump) as it happens even when it's off.

After reassembling everything the problem seems to have gotten even worse. It looks like snow flurries blowing in the tank, like a light snowglobe (except these are tiny bubbles).

Any ideas? The pump is deep enough that it's not creating a whirlpool and pulling air in.

rkpetersen · Dec 15, 2018

Does it happen at different pump output levels? And is there any obstruction to the pump inlet?

Idoc · Dec 15, 2018

There's a leak somewhere in the return line to the tank.

Dry off all the return line pipes and connections. Then shut off your pump. You might then notice a small amount of moisture along the return line that may give away the leak location. If you can't find it, you'll need to re-seal all connections. Do you have any unions? Possibly a bad seal, if so.

theKoolAidMan · Dec 15, 2018

Idoc said:
There's a leak somewhere in the return line to the tank.

Dry off all the return line pipes and connections. Then shut off your pump. You might then notice a small amount of moisture along the return line that may give away the leak location. If you can't find it, you'll need to re-seal all connections. Do you have any unions? Possibly a bad seal, if so.

I'll check. My prime suspect is the seal going from the hose barb to the bottom of the overflow/bottom of the tank. This is a problem with the Reefers. My Reefer 450 had a leak there when I set it up originally. Had to use teflon tape to fix it. I don't notice a leak on the Reefer nano, but there probably is a very very tiny one.