In my display refugium, I run a D that sits by the inlet of my skimmer, both running two catalysts and currently 6% as I can't get 9% currently, I have been using them for about 10 years now and would never run a tank without one.
I also run a mini in my Evo 52 Litre, same combo as above. :)
I also run a mini in my Evo 52 Litre, same combo as above. :)
