Tunze 9001 skimmer issue

Reef. · Apr 3, 2025

Hi, think it’s called the “impeller cover”? It keeps coming off the pump body, maybe once a week, is they a way to stop this from happening? Thanks

rvitko · Apr 3, 2025

Is there a certain scenario it pops off in? It should just click into place, it is not a very tight fit, it will come off if you pull the pump down, but it should stay in just normal operation. Make sure the fins are aligned with the small notches in the pump when you push it on.

Reef. · Apr 3, 2025

rvitko said:
Is there a certain scenario it pops off in? It should just click into place, it is not a very tight fit, it will come off if you pull the pump down, but it should stay in just normal operation. Make sure the fins are aligned with the small notches in the pump when you push it on.

No specific scenario for it to happen, guess it’s just working loosing. Not a big issue as it’s easy to replace.

Another quick question if you don’t mind, would you say the DC model is worse upgrading too? Reason being, I have the air fully open on the non dc model, the skimmer as low down as possible but yet bubbles are struggling to get over the top, I’m thinking with the Dc model I could up the power slightly to get the bubbles over the top of the cup more reliably, is my theory correct? Thanks.

rvitko · Apr 4, 2025

How old is this skimmer? Generally yes, the DC one can skim much wetter, but the AC one can skim fairly wet as well, my hunch is something is going on with the air intake, is the air line the original? Are you sure there is no tension on the line resulting in kinking, if the line was extended or replaced this can be a cause of issues with either model and this tension can pull the impeller cover off the pump. Are you sure the air intake nipple on the impeller cover is not obstructed by salt creep?

Reef. · Apr 4, 2025

rvitko said:
How old is this skimmer? Generally yes, the DC one can skim much wetter, but the AC one can skim fairly wet as well, my hunch is something is going on with the air intake, is the air line the original? Are you sure there is no tension on the line resulting in kinking, if the line was extended or replaced this can be a cause of issues with either model and this tension can pull the impeller cover off the pump. Are you sure the air intake nipple on the impeller cover is not obstructed by salt creep?

Hardly used, it’s the original tubing and I you the magnet holder so no kinks in the tubing, I’ve removed the tubing to check it’s clear, comes off about once weekly, think it’s just working loose as the grooves it sits in are very shallow…think I’ll give the dc a try as skimming litter wetter I’d probably going to work better for me.

I’ll definitely recheck your suggestions though, thanks for the reply.

Reef. · Apr 4, 2025

Found the issue of why the bubbles were hardly making it over the top of the collection cup, there was a piece of algae blocking the pump inlet, working great now, not sure if that is related to the impeller cover working loose?…thanks for making me recheck the skimmer.