How a HMF (Hamburg matten filter) Works

Mattenfilter -- air or powerhead?

Hamburg Mattenfilter for quarantine?

HMF Hamburger Mattenfilter mit 3cm Matte PPI 30 –

HAMBURG MATTEN BIO Mobile sponge filter fish shrimp fry black breed 10x10x34cm £25.99 - PicClick UK

HMF Hamburger Mattenfilter mit 3cm Matte PPI 30 –

Thoughts about using the Hamburg Mattenfilter (HMF)

Hamburg Matten Aquarium Filter

aquarium - What's the purpose of a gravel blockage of a mat filter? - Pets Stack Exchange

Hamburg Mattenfilter for quarantine?

The HMF – What's That? — Seriously Fish

Hamburg Matten Filters are space saving, non leaking and supremely efficient. HMF`s do better when not cleaned.

The HMF – What's That? — Seriously Fish

Building a Hamburger Matten Filter (HMF) for an Aquarium : 4 Steps - Instructables