Anyone Else Having Problems With Fluval U Series Filters?

[yabadaba]

Hi, was wondering whether it's just a case of bad luck that I've been having with my U3 filters or could it be bad design?

I've got a U3 in my community tank (110L) and it was fine for a few months but then the flow reduced significantly despite regularly rinsing out/changing the media. Last week I noticed that the flow had stopped almost completely so I removed the filter and gave the whole thing (not just the media) a good clean out in a bucket full of tank water. That included using a large syringe to 'pressure clean' all the internal waterways. A fair amount of 'crud' was left in the bucket and to my relief the filter worked superbly when I plugged it back in - the flow was really strong, like I recall it being when it was new. But, after checking again this evening the flow is down to around 50% again - that's only 1 week after a thorough cleaning.

My son also has a U3, which is newer than mine and whilst there are no issues with flow (yet) on that one it shares a different problem with my U3. The majority of times when either are powered-up after having been removed from the water (for cleaning or tank maintenance) they fail to start. I assume this is an air-lock issue, but it can take an awful lot of coaxing to get them to start up again (inverting to force air out repeatedley / removing the impeller section and replacing) to the point where you begin to think the motor has actually failed.

Anyway, I really can't live my U3 anymore because of the flow issue, but would be prepared to simply buy another one if I thought it was just a bad example that I had. That would make it all pretty straightforward as I could just transfer my mature media across and not get any mini-cycle issues. Has anyone else here had problems with their U3 (or other U series filters)? Also, what would be a good (internal) alternative - an Eheim Aquaball maybe?

 

[Macko1968]

I've been running two for about 4 months now with no issues at all.

 

[yabadaba]

Well, to be honest I think I've just been unlucky with mine, particularly in respect to the flow reducing. When I've asked in my local fish shops the staff have always said that nobody has complained yet about the U series. I've just bought an Eheim Aquaball 180, so I'll be able to compare shortly.

 

[Bluetooth]

my gf has a u2 and i have a u3, her u2 recently clogged but thats cause it hadnt been cleaned since we got it about 3 months ago, apart from that no issues with the u2.

Had my u3 about 3 weeks or so now and had no problems with it and its in a discus tank so not exactly clean fish just probably a bad one

 

[ZoddyZod]

I've had mine for about 6 months and have had to clean it out to improve the flow only twice, so not too bad.

Do you have large waste producing fish, or maybe lots of loose plant matter that could be clogging it up quicker than expected?

 

[GrubbyGirl]

I'm having to a similar problem with my U2 in my 60l tank, so much so I now have a backup filter in there. The first thing you notice is that it becomes noisier and the flow significantly rediced, cleaning the foams is not enough in fact the first time I cleaned the media and put it back it didn't work at all, I had to clean the whole thing. Nowhere near as good as the plus filter imho

 

[GrubbyGirl]

Just as I was going to bed I noticed it wasn't working again. I've taken it to bits and completely cleaned it again and I still can't get a good flow - can't get the venturi to work at all. This is hopless having to do this every couple of days!

 

[yabadaba]

Just as I was going to bed I noticed it wasn't working again. I've taken it to bits and completely cleaned it again and I still can't get a good flow - can't get the venturi to work at all. This is hopless having to do this every couple of days!

Just in case it's of any help, I've had a google around since posting and have found a number of other reports of the impeller not starting up again after a water change or filter clean. The workaround seems to be to remove the bottom motor section and just give the impeller a tap or a jolt. Though if your's was already running then it sounds like it might be clogged again.

Fitted an Eheim Aquaball 130 in my son's 63L tank this morning and initial impressions are good. The flow is a little stronger than the U3 (when it's working at its max) and the head is basically a large ball in a socket that makes it really easy to direct the flow. It's just as quiet as the U3, too. The only downside is that it seems to hold slightly less media than the U3 as I wasn't able to fit all that came out of the U3 into it. I'm currently 'seeding' an Aquaball 180 in my 110L community tank and that's got a slightly larger media capacity than the U3 and a much stronger flow (that can be restricted if wanted). To be honest I'm tempted to permamently leave 2 filters running in that tank because the water is now the clearest I've ever seen it ...even though the U3 is only running at around 50%

 

[yabadaba]

I've had mine for about 6 months and have had to clean it out to improve the flow only twice, so not too bad.

Do you have large waste producing fish, or maybe lots of loose plant matter that could be clogging it up quicker than expected?

Both U3's are in pretty regular, lightly planted community tanks with standard type stocking...cory's rams, otos, SAE, Paradise fish, small shrimp, snails. Mainly feed frozen foods, Tetra Prima, and algae wafers with the occasional bit of spinach or cucumber thrown in. Any uneaten veg is removed and both tanks are regularly vaccumed.

 

[GrubbyGirl]

that may be my problem, mine is in my juvenile L144 tank with 12 of those poop macines in it!! anyone want to swap a 3 month old U2 for a 2 plus?