Fleece roller mat

I am curious what everyone's opinion is on fleece roller filters, especially for nano reefs. I think the idea of automating mechanical filtration is great, but there's not many options for nano reef tanks that have a small sump. Is there just no demand for a small roller filter so manufacturers don't offer a small one? I've seen the Klir filter system for dropping into 4 inch sock filter openings but the reviews aren't great and I'm wanting something that is even smaller or cheaper. I've thought about building my own controlled by a microcontroller and I'm wondering if there's much interest and if it would be worth the effort to create and share plans for others to make one.

Edited by naffin01 - July 10 2022 at 10:12pm

It's a 20 gal tank with a 6 gal custom sump so I don't have a lot of space for something with a large footprint. The Klir retrofit unit would work for me since most of the space is vertical but not sure it’s worth the price tag with all the problems people have with those retrofit units. By retrofit, I mean it sits in the 4 inch hole previously used for a sock filter. 

I've got the Klir DI-7 and I've been pretty happy with it.  Been running for a year.  It's on my 120, and I replace a roll every 6-8 weeks.  It's a hassle swapping rolls, but way less hassle than filter socks.  I'd buy one again.