Fish Getting Trapped Behind Filter

[Haveagojoe]

Iv'e got the Fluval U3 internal filter and everywhere I've read they seem to get good reviews but to me they have one pitfall, fish seem to get trapped behind it.The filter sits on a cradle that sticks to the glass so as you can unhinge it to gain acssess to the filter media and thats where the fish go!
I've lost a female guppy,azebra dfanio and by the looks of it I'm going to lose two zebra loach,I haven't seen them for two days untill I moved the filter tonight and they were there, they seem to be able to get in the gap but not get out, there body is badly damaged with what looks like they have been struggling to get out and can't,thev'e got lacerations along their flanks and look in a sorry state but as soon as you put the filter back in position they go back in there, exactly the same thing happened to the guppy and a zebra danio.
The only answer I can see is to leave the filter in the "unhinged" position so they can't get in there but that then completly alters the flow around the tank.
Has anyone else encountered this problem I would be really interested to hear if others have had this.

 

[GavinB]

apparently this is a common issue.

Its probably worth putting some filter floss behind to stop the fish getting in.

 

[Carlovel1]

Iv'e got the Fluval U3 internal filter and everywhere I've read they seem to get good reviews but to me they have one pitfall, fish seem to get trapped behind it.The filter sits on a cradle that sticks to the glass so as you can unhinge it to gain acssess to the filter media and thats where the fish go!
I've lost a female guppy,azebra dfanio and by the looks of it I'm going to lose two zebra loach,I haven't seen them for two days untill I moved the filter tonight and they were there, they seem to be able to get in the gap but not get out, there body is badly damaged with what looks like they have been struggling to get out and can't,thev'e got lacerations along their flanks and look in a sorry state but as soon as you put the filter back in position they go back in there, exactly the same thing happened to the guppy and a zebra danio.
The only answer I can see is to leave the filter in the "unhinged" position so they can't get in there but that then completly alters the flow around the tank.
Has anyone else encountered this problem I would be really interested to hear if others have had this.

Used to have this filter 1 year ago. Lost quite a lot of Loaches and Tetras to it, which was disappointing. Also a lot of gunk accumulates behind the filter. IMO its a good filter with serious design flaw. Saying that, I placed some McDonalds drink straws behind the filter and I had less fish dying. Since then, I've upgraded to an external filter so I dont have to worry about losing fish

 

[Proxo]

I've got this filter and had it for about 6months now, i've never had this problem yet *touch wood*
But thanks for the heads up, i can keep an eye out now

 

[sXeLifer]

I have the U4 so its generally the same filter just a bit bigger, my thin stripes dart in and out but have never been stuck I'll keep an eye on them though which is easy to do as my tank is at a 45 degree angle to "my tv seat"

 

[Haveagojoe]

Iv'e got the Fluval U3 internal filter and everywhere I've read they seem to get good reviews but to me they have one pitfall, fish seem to get trapped behind it.The filter sits on a cradle that sticks to the glass so as you can unhinge it to gain acssess to the filter media and thats where the fish go!
I've lost a female guppy,azebra dfanio and by the looks of it I'm going to lose two zebra loach,I haven't seen them for two days untill I moved the filter tonight and they were there, they seem to be able to get in the gap but not get out, there body is badly damaged with what looks like they have been struggling to get out and can't,thev'e got lacerations along their flanks and look in a sorry state but as soon as you put the filter back in position they go back in there, exactly the same thing happened to the guppy and a zebra danio.
The only answer I can see is to leave the filter in the "unhinged" position so they can't get in there but that then completly alters the flow around the tank.
Has anyone else encountered this problem I would be really interested to hear if others have had this.

Used to have this filter 1 year ago. Lost quite a lot of Loaches and Tetras to it, which was disappointing. Also a lot of gunk accumulates behind the filter. IMO its a good filter with serious design flaw. Saying that, I placed some McDonalds drink straws behind the filter and I had less fish dying. Since then, I've upgraded to an external filter so I dont have to worry about losing fish

Great idea I'll give that a go

 

[Joshwainwright]

I've just got the Fluval U3 with my new Roma 125. I don't know if I should use it or not.

 

[Proxo]

I've just got the Fluval U3 with my new Roma 125. I don't know if I should use it or not.

Well i personally would use it & if u did end up with problems
of fish getting stuck behind (what not everybody does) you can then change?

 

[FishAreFriendsNotFood10]

nothing gets stuck behind mine lol i find my amano shrimp there at times tho but they come and go as they please

 

[Joshwainwright]

nothing gets stuck behind mine lol i find my amano shrimp there at times tho but they come and go as they please

I suppose it depends on the size of your fish. Some fish will be so small they can easily swim through the gap, some fish will be so big they can't get into the gap and finally, some fish will be the perfect size to be able to get into the gap and get stuck.

 

[lilfishie]

My fish are fine with it, the largest being my L52 at 5", she sits behind it a lot but can easily get out

 

[FishAreFriendsNotFood10]

i have cardinal tetras and honey gouramis which dont seem to fit behind there just for info