Advice needed, I decided to clean up one of the nano streams, so put it in a tub in a 1% hydrochloric acid solution and ran it. Meant to turn it off after a couple of hours but forgot and left it going for a day or so.

Now it's really noisy i can't put it back in the tank. I've pulled it apart but there is nothing obviously wrong that can be seen.

Advice anyone?

How noisey?

Assuming theres nothing obvious (like broken shaft) then it may just need to develop a slime coat again? When I first got mine they were quite noisey, like a vibration type noise, but after about a week and a bit of slime built up they're as quiet as a mouse now.

Hmmm... Yes, well it's pretty noisy, more so than when it was new.

But I'll take your advice & stick it in the tank & see what happens. Long as my wife doesn't get too stroppy about the noise!

i found one of my nanos had a bit of a vibration noise when it wasn't seated in the magnetic clip correctly, also when one of my clips broke it allowed the powerhead to vibrate more against the glass, maybe check to make sure the nano clip hasn't broken

Had a shaft shear recently,caused major noise,due imbalance.Took a little time to diagnose as the shaft remained semi connected in the spindle.Reef was kind enough to courier out a new shaft the next day,excellent service..

Ha! Well you are onto it Westy, turned out the shaft was much thinner than it should be I think the acid must have eaten into it. So I won't do that again!

I pulled the shaft & it snapped at the bottom so I'll have to talk to Reef.

Thanks everyone for the help!