Overall I had good germination with my ADBLPS seeds. I had no germination with Pterocactus araucanus, Pterocactus megliolii and Puna bonnieae. I did —at a later stage— order another batch of Pterocactus seeds from ADBLPS and had very good results. I sowed P. araucanus, australis, fischeri, gonjianii, hickenii, megliolii, reticulatus and tuberosus. The difference with the first batch was a slightly lower temperature, 25°C instead of 28°C. The seeds were sterilized for 15' in a solution of 9 parts water : 1 part bleach. I also left out any organic material in my sowing substrate the second time around. I ventilate quite early, but bit by bit. As soon as the baggie is completely open and the soil has dried up I water and fertilize intermittently.
Peniocereus viperinus germinated very quickly and the seedlings are already too big for the propagation box.
Setiechinopsis mirabilis and Echinocereus poselgeri also germinated soon, but it takes a while before they develop their first spines. 2 months give or take.
4 out 20 Echinomastus mariposensis germinated, but they appear to need fresh air soon after. One got some orange spots, but it will outgrow these I hope.
One of the things I learned this year is —if you sow in a propagation box— to sow genera which require similar conditions. Instead of mixing a lot of different thing...
I'm also experimenting with sowing substrate and with my latest composition (6 EXPANDED CLAY : 1 BENTONITE : 4 QUARTZ GRIT) I had no issues whatsoever with algae or mold. I don't sterilize my soil and some pots have been in a ziplock bag for several months now. I bought the expanded clay in a pet store. It's used for aquariums and has a grain of 1-2mm. I like it, but it's not cheap.