ReefMat Nano on Waterbox 35.2

[Reefer911]

I’m having trouble getting this thing dialed in. I let it go a while before deciding that it’s not operating properly because I only have two fish. But the fleece is covered in waste material and I am having problems with high nutrients.
The pic below is the inside of the filter housing with the clean roll removed. The red arrow indicates water flow. The red circle is the auto advance sensor. And this is the problem…the water level doesn’t rise to the auto advance sensors because (maybe) the water freely flows out (red arrow). Seems like there should be a higher wall at the outlet that matches up with the auto advance sensors.
Can anyone offer any insight or help on this? I need to get the nutrients in check.

The yellow circle indicates the high water sensor

BTW, I could raise my ATO to get closer to the sensors, and I have, but there still needs to be an additional water rise within the filter housing to trigger the auto advance.

 

[Rocks reef]

Is there a way to put a small piece of acrylic by the water flow (red arrow) to raise the water level? Are you able to adjust or trim the "feet" on the Reefmat to lower it in the water column?

 

[Reefer911]

Is there a way to put a small piece of acrylic by the water flow (red arrow) to raise the water level? Are you able to adjust or trim the "feet" on the Reefmat to lower it in the water column?

Researching more, and now that I really think about it, water shouldn’t be exiting where the red arrow is. It should be exiting through the filter roll. Duh, I guess. But no, the filter is sitting on a filter sock bracket so I can’t lower it any more.
I really wish I could get this figured out; I’m manually advancing the roll until I do