Nano 15G/60L - Using Live Rocks in filter or not

[Sdiesel77]

Hi Guys,
My nano tank 15G/60L has been running great for over a year, water parameters look alright however I start noticing a caulerpa racemosa invasion and some dino.
I am using crushed live rocks in my back filter and was wondering if I should keep it this way or if it could be generating nitrates/phosphates.
What's your opinion, should I keep it this way or should I remove it?

Here is a drawing of my back filter

 

[saltyfilmfolks]

I would definitely clean it out, and take a look.

 

[Sdiesel77]

I finally clean the crushed rocks with tank water and the chambers. I'd say it was well worth it, really dirty out there! ☠
Now I'm wondering, sound I keep the rocks in the second chamber or just the filter media..?

 

[saltyfilmfolks]

I personally would let the rock and sand IN the tank be the bio filter.
In the last months I had my JBJ cube, I only did water changes from the back, just to keep the funk down.