Help with small cluster drops

I've been running delirium with Mania and Paranoia scarabs. I've got a full tab of large and medium clusters, but I don't have even one small cluster. Are they really that rare, or am I doing something wrong?
I'm spamming T16 maps with almost all the delirium nodes, plus a bunch of Maven nodes. Usually ~100% qual + corruption.

Help? how do I find small clusters?

Check your filter, Filterblade hide common small clusters starting with the "Very Strict" filter setting (if I'm not mistaking).

But yes, they seem to be rare, I dunno why, most are garbage. I run delirium mirror with Unending Nightmare in Standard and I have only seen a couple in 50 maps or something. I'm also flooded with medium clusters.

Yes, first thing I checked. Loot filter is working as expected. I'm just not getting any drops. I get 2-4 Medium/Large clusters when delirium ends, but haven't seen a small yet.