Fluval Evo intank media basket flow problems

[Timbo13]

Hi Reefers,

I'm not sure how long this has been going on but I think it's only been happening recently. I have a Fluval Evo 13.5 with InTank media baskets in both chambers 1and 2. The water is meant to cascade out of the display onto the floss on the top of chamber 1. It doesn't. It flows for a while (a few hours) then just blocks up to flow over the top of the InTank basket. At the moment the tank is fallow (had a parasite in the tank), so there is almost 0 debris in the water. I've tried cutting the filter pad in half so it's not as thick, changing it out twice a day etc.. Even with the filter pad still looking new and white it backs up. I though it may have been kalkwasser blocking it as I've recently started adding it to my ATO. I cleaned out the ATO and went back to plain old RODI water and it still backs up... I've pulled everything out of the back 3 chambers and cleaned it out. If you look at the pictures below: Picture 1: new filter pad in and good overflow into the basket. Picture 2: aerial view of picture 1. Picture 3: Already filling up after ~20 minutes. Picture 4: overflowing after and hour or so. Obviously I want the water flowing through the pad into the media for optimal filtration.
Anyone have any ideas or experience with this problem

?

 

[reefiniteasy]

Is there anything in the other chambers of the basket? What kind of filter pad?

 

[Timbo13]

In chamber 1: Just some filter pad I bought from my LFS on the top. )I've included a photo) Chemipure blue nano pack in the middle and ceramic rings on the bottom. In chamber 2 just seachem matrix. Thanks for asking

 

[reefiniteasy]

Have you cleaned the return to make sure it’s not blocked by something?

 

[Timbo13]

Yeah, I pulled everything out of the back chambers (return, InTank media baskets, heater) and cleaned it. There's no problem with the return pump. Looking at the 3 chambers it looks like there is nothing restrict the flow.

 

[reefiniteasy]

How does it flow without the pad?

 

[Timbo13]

I'll need to check that when I get home from work. From what I remember the water level was lightly raised but nothing drastic when removing the filter. The flow through chambers 2 and 3 must be fine because when chamber 1 overflows, chamber 2 is only slightly raised and chamber 3 still sits at the mark for my ATO top off. It's definitely something to do with chamber 1. Could it be a build up of something (bacteria or detritus) in the ceramic rings in the bottom of the first chamber restricting flow? I have kept the same rings in there since I started the tank in October of last year...

 

[reefiniteasy]

1. Could it be a build up of something (bacteria or detritus) in the ceramic rings in the bottom of the first chamber restricting flow? I have kept the same rings in there since I started the tank in October of last year...

It could definitely be because of f the rings if they’re dirty. Rinse them in some saltwater to clean them up.

 

[Timbo13]

Cheers. I'll give them a wash next water change

 

[Timbo13]

@reefineasy. I took all the rings out and washed them in my dirty water when I did a water change. It seems to have fixed the flow issue. It's been over an hour and the chamber hasn't been overflowing. I also lowered the ATO top off line in chamber 3 to give a bit more wriggle room with the water level.
Thanks for helping out!!